Nothing wrong with cranberries

Sure there is nothing wrong with eating cranberries. Although the same thing could be said of consuming any fruits as they are all considered healthy so there is some competition. That might be the reason why the Cranberry Institute felt obliged to provide funding for two recent studies showing the beneficial effects of cranberry consumption on memory and blood flow.

But can you believe the conclusions of studies tainted by respective industry contributions? Read on so you can judge for yourself.

Cranberries might improve cardiovascular health

The Cranberry Institute provided financial support to a recent clinical trial which found that daily consumption of cranberries for one month improved cardiovascular function in healthy men.

The study included 45 healthy men who consumed 9g of freeze-dried cranberry powder equivalent to a cup of 100g of fresh cranberries per day or a placebo for one month. Incredibly, the study found that those consuming cranberries showed significant improvements in flow-mediated dilation of blood vessels already two hours after first consumption and after one month of daily consumption indicating both immediate and long-term benefits. The researchers claimed that consumption of cranberries as part of a healthy diet can help reduce the risk of cardiovascular disease by improving blood vessel function.

Sure there is evidence that links polyphenols from berries with heart health benefits. And as it happens, cranberries are rich in unique proanthocyanidins that have distinct properties compared to polyphenols found in some other fruits.

Cranberries might also improve memory

The Cranberry Institute wanted more good news by financially supporting a study investigating the impact of cranberry consumption on memory and brain function. Past studies have shown that higher dietary flavonoid intake is associated with slower rates of cognitive decline and dementia. And foods rich in anthocyanins and proanthocyanidins, which give berries their red, blue, or purple colour, have been found to improve cognition.

Thus, the commercially funded research team from the University of East Anglia (UK) investigated the impact of eating cranberries for 12 weeks on brain function and cholesterol among 60 cognitively healthy participants between 50 to 80 years old. Again, half of the participants consumed freeze-dried cranberry powder, equivalent to a cup of 100g of fresh cranberries, daily. The other half consumed a placebo.

The study, one of the first to examine cranberries and their long-term impact on cognition and brain health, showed that consuming cranberries significantly improved memory of everyday events (visual episodic memory), neural functioning and delivery of blood to the brain (brain perfusion).

The cranberry group also exhibited a significant decrease in LDL or ‘bad’ cholesterol levels, known to contribute to the thickening or hardening of the arteries caused by a build-up of plaque. The researchers claimed that the potentially improved vascular health may have in part contributed to the improvement in brain perfusion and cognition.

Of course the researchers considered the findings encouraging, especially as a relatively short 12-week cranberry intervention was able to produce significant improvements in memory and neural function. They see it as an important foundation for future research in the area of cranberries and neurological health.

Ocean Spray Inc. also at it

The U.S. cranberry juice giant, Ocean Spray Inc., has spent millions of dollars funding research to try to prove the health aspects of consuming cranberry juice. There has long been a myth that cranberry juice can prevent urinary tract infections (UTIs). Back in the day, before antibiotics were a thing, acidification of the urine was a recommended treatment for UTI. It was believed that because cranberries are acidic, they would make urine more acidic to fight off bacteria. This was attributed to formation of hippuric acid through metabolism of the quinic acid present in cranberry juice.

Unfortunately, later studies reported that the concentration of hippuric acid in the urine was insufficient for an antibacterial effect unless very large volumes of cranberry juice were ingested.

Subsequently, proanthocyanidins present in cranberries as well as blueberries were reported to inhibit binding of the type 1 P-fimbriae of Escherichia coli to uroepithelial cells, preventing bacterial adherence within the urinary tract.

However, researchers from the University of Manitoba found that the two proposed mechanisms for a beneficial effect of cranberries on UTIs had not yet been shown to have a role in human infection.

EFSA and FDA dismisses cranberry health claims

In 2009, Ocean Spray Inc. submitted a health claim for cranberry juice to the European Food Safety Authority (EFSA) supported by several scientific studies. However, the EFSA Panel concluded that the evidence provided was not sufficient to establish a cause and effect relationship between the consumption of Ocean Spray cranberry products and the reduction of the risk of UTIs in women by inhibiting the adhesion of certain bacteria in the urinary tract.

In 2017, Ocean Spray Cranberries Inc. tried again, this time logging a health claim for cranberry juice with the U.S. Food and Drug Administration (FDA). After reviewing the petition and other evidence related to the proposed health claim, the FDA determined that the scientific evidence supporting the claim did not meet the “significant scientific agreement” standard required for an authorized health claim. However, at the same time FDA announced that it does not intend to object to the use of certain ‘qualified health claims’ regarding consuming certain cranberry products and a reduced risk of recurrent urinary tract infection (UTI) in healthy women. As long as a qualifying statement was included on the label stating that FDA has concluded that the scientific evidence supporting this claim is limited and inconsistent.

Not looking convincing?

It’s up to you to decide what you think. As I said in the beginning there is nothing wrong in eating cranberries as they would be as healthy as any other berries.

To help you make up your mind here is a quote from the well known nutrition expert Marion Nestle:

“Without even getting into whether cranberry powder is equivalent to cranberries, whether anyone can eat cranberries without adding their weight in sugar, or whether any other fruit might have similar effects, we should ask whether it makes any sense at all to think that any one single food could boost memory and prevent dementia in the elderly.”

So there you have it.

Does a yoghurt a day keep diabetes away?

Even if this probably is a good news story, an initial caveat is justified. Establishing a causal link between consumption of an individual food product, like yoghurt, and a specific disease is fraught with challenges. It could be a statistical anomaly or covariant factors that were responsible for the effects but not possible to be eliminated during the statistical analysis. In this study, also the authors point out that to confirm the findings controlled studies would be necessary.

With this caveat out of the way, researchers from Harvard School of Public Health found that a high intake of yoghurt seemed to be associated with an 18% lower risk of developing type 2 diabetes. If true, it shows the benefit of having yoghurt as part of a healthy diet.

Facts about the disease

Type 2 diabetes is a chronic condition that occurs when the body doesn’t produce enough insulin, or the body’s cells develop resistance to insulin. The condition has a strong genetic background and is also often associated with modifiable lifestyle risk factors like an unhealthy diet and lack of exercise. Type 2 diabetes usually develops in middle age adults but is increasingly occurring in younger age groups. The Harvard researchers pointed out that about 366 million people are affected by type 2 diabetes worldwide and it is estimated that this will increase to 552 million people by 2030, which puts pressure on global healthcare systems.

The disease develops over a long period of time with a progressive insulin resistance. As insulin is increasingly ineffective at managing the blood glucose levels, the pancreas responds by producing greater and greater amounts of insulin wearing the insulin-producing cells out. By the time someone is diagnosed with type 2 diabetes, they have lost 50 – 70% of their insulin-producing cells. This means type 2 diabetes is a combination of insulin resistance and not enough insulin.

It might be possible to significantly slow or even halt the progression of the condition by increasing the amount of physical activity and adopting a healthier diet. And here yoghurt might be a part of a healthy diet.

Facts about the study

The Harvard researchers pooled the results of three large prospective cohort studies that have been following the medical history and lifestyle habits of health professionals in the USA for different purposes. At the beginning participants had been asked to complete a questionnaire to gather baseline information on diet, lifestyle and occurrence of chronic disease. Participants were followed up every two years for 16-30 years depending on cohort with a follow-up rate of more than 90 per cent.

In this particular analysis of the cohorts results, the researchers excluded participants with diabetes, cardiovascular disease or cancer at baseline as well as lack of response to the question on dairy consumption as this was the target for the analysis. This resulted in a coverage of almost 195,000 remaining participants aged between 25 to 75 years for the analysis.

Study benefits included the large sample size, high rates of follow up and repeated assessment of dietary and lifestyle factors.

What did they find?

Within the three cohorts 15,156 cases of type 2 diabetes were identified during the follow-up period. While adjusting for chronic disease risk factors such as age and BMI as well as dietary factors, the researchers found that total dairy consumption had no association with the risk of developing type 2 diabetes. They then looked at consumption of individual dairy products, such as skimmed milk, cheese, whole milk and yoghurt and found that high consumption of yoghurt was associated with a lower risk of developing type 2 diabetes.

To confirm their results the authors conducted a meta-analysis, incorporating their results with results from a few other published studies that also investigated the association between dairy products and type 2 diabetes. Overall they concluded that consumption of one 28g serving of yoghurt per day was associated with an 18% lower risk of type 2 diabetes.

So overall some good news.

What to think of the findings?

While an 18% improvement might not sound that much every bit helps. It is extremely rare to find any food that can have a major impact on a particular health condition. What comes to mind is vitamin C rich foods like oranges that can fully protect against scurvy, but not much else. An overall healthy diet is more important than individual food components and of course yoghurt can be part of that healthy diet.

There are other support for yoghurt consumption. In 1904, four years before he jointly won the Nobel Prize in Physiology or Medicine for his research in immunology, Professor Elie Metchnikoff gave a public lecture in Paris. He suggested that beneficial healthy bacteria could be cultivated in the gut by eating yoghurt or other types of sour milk. He had surveyed 36 countries and found that more people lived to the age of 100 in Bulgaria, a high yoghurt consuming country, than anywhere else.

Later research has shown that probiotic bacteria found in yoghurt improves fat profiles and antioxidant status in people with type 2 diabetes and suggest this could have a risk-lowering effect in developing the condition.

You be the final judge, but a little yogurt every day is probably not a bad thing!

The sugar conundrum

In February 2022, EFSA published a safety assessment of sugars in the diet and their potential links to health problems. The impact of excessive sugar intake has long been a concern for health professionals, but what to do about it is not so clear. The EFSA opinion concluded that intakes of added and free sugars should be as low as possible as part of a nutritionally adequate diet, but despite reviewing about 30,000 scientific articles on the topic uncertainty remained about more specific recommendations. So not much progress.

So where do we stand?

Sugars are commonly defined as monosaccharides like glucose and fructose, both of which occur naturally in honey, many fruits, and some vegetables, and disaccharides like table sugar (sucrose, extracted from sugarcane or sugar beets) and lactose abundant in milk. Sugars are part of the carbohydrate complex of chemicals. They serve as the main energy source for the body. Carbohydrates are also components of complex molecules that perform numerous key roles in living organisms. As carbohydrates coexists with essential nutrients in many foods their consumption is inescapable. Thereby the conundrum. How to limit their consumption while achieving an adequate intake of essential nutrients.

Adding to the confusion are the different categories and sources of sugars, which can be naturally occurring or added. Total sugars comprise all mono- and disaccharides, regardless of source, including those naturally present in fruit, vegetables, and milk. Added sugars are refined sugars used in food preparation and as table sugar. Free sugars includes added sugars plus those naturally present in honey and syrups, as well as in unsweetened fruit and vegetable juices.

To date, there has been little evidence-based analysis of the scientific basis for these different sugar classifications or implications of their adoption for consumer communication and nutrition labelling.

All clear now, or not? Let’s come back to this.

Health impact of excessive sugar intake

It is clear that sugars have a negative impact on health. Consumption of sugars is a known cause of dental caries. Evidence also links excessive consumption of sugars to some chronic metabolic diseases, including obesity, non-alcoholic fatty liver disease, and type 2 diabetes.

The goal of the EFSA scientific opinion was to establish a tolerable upper intake level for dietary sugars on the basis of available data on chronic metabolic diseases, pregnancy-related endpoints and dental caries. That is the maximum level of usual daily intake of sugars from all dietary sources judged to be unlikely to pose a risk of adverse health effects to humans. A threshold should be able to be identified from the scientific literature below which no risk from consumption of dietary sugars is expected for the general population, and above which the risk of adverse health effects, including risk of disease, increases.

Current sugar intake recommendations

There have been previous attempts to establish thresholds. In 2015, major evidence-based risk assessments with quantitative recommendations for sugar intakes were published by three major independent authorities. The World Health Organization suggested an energy intake of less than 10% from free sugars with a further reduction to below 5% considered beneficial. The United Kingdom Scientific Advisory Committee on Nutrition was a bit firmer with the recommended energy intake from free sugars at 5% or less. The United States Dietary Guidelines Advisory Committee based their recommendation on an energy intake of 10% or less from added sugars.

There is thus a bit of confusion about whether recommendations should be based on free or added sugars and at what level. This variation is also apparent in recommendations from other international authorities with recommended levels of added or free sugars hovering around the 10% of energy intake. However, this is not helping consumers as none seems to base their recommendations on “total” sugars, although globally that is most commonly used for labelling and informing consumers about the sugar contents of foods and beverages.

How to solve the conundrum

So the request to EFSA for a review of the situation was certainly justified as uncertainty remained. Could the latest science help in differentiating between the health impact of added, free and total sugars? Could scientific findings point to a justification for nominating a safe threshold level? How can food labelling of sugar content assist consumers in avoiding products with excessive sugars?

In answer to the first question there was little difference in health impact between added and free sugar consumption. European data indicated that intake of fruit juices was the main difference. Others have looked at evidence linking total compared with added or free sugars with weight gain or energy intake, type 2 diabetes, and dental caries. The relations were weakest for total sugars and most consistent for dietary sources corresponding to free sugars. 

In answer to the second question it was not possible to nominate a safe threshold level based on science as there was a linear relationship between the amount of sugars consumed and its impact on health. That is the more sugar consumed the higher the risk of disease with the opposite true as well all the way down to zero consumption, given that the overall diet remained nutritionally adequate. The scientific uncertainty of potential health impact was particularly high when the intake of sugars contributed to less than 10% of energy intake.

In answer to the third question it seems we have to stick to the current Codex Alimentarius Guidelines on Nutrition Labelling, which require the labelling of total but not added or free sugars. Adoption of free sugars for labelling purposes would carry challenges related to implementation, including consumer understanding, consensus on specifications, and the current lack of analytical capabilities to differentiate between naturally occurring and added sugar.

So what should you do?

If you want to keep your sugar consumption as low as possible you can be guided by the amount of total sugar declared on the food label while considering the importance of other nutrients in the food. Don’t exclude dairy products and intact fruit and vegetables from your diet just because they naturally contain sugars. If you consume less than 50g of sugars a day you should be below the recommendation for sugars to provide less than 10% of overall energy. For reference, 50g of sugars is equivalent to about 4 tablespoons of table sugar and not as challenging as it might sound.

It can also help to keep a keen eye on food groups contributing most to the intake of added and free sugars which in European countries were table sugar, honey, syrups, confectionery and water-based sweet desserts, followed by some beverages and fine bakery wares. In infants, children and adolescents, sweetened milk and dairy products were also major contributors to mean intakes of added and free sugars.

Beneficial basil – or not!

Fruit and vegetables are important parts of the daily diet. They are low in fat, salt and sugar and a good source of dietary fibre. Fruits and vegetables contain many vitamins and minerals that are good for your health. They also importantly contain a range of exciting phytochemicals – biologically active substances that can provide protection from some diseases. Now it’s time to cover fenchol – a phytochemical found in basil.

Fenchol is a natural compound abundant in some plants including basil. It is used extensively in the perfume industry, as well as in the food processing industry. It has a smell of pine, lemon and camphor. Fenchol has many known medicinal properties, most notably antibacterial, antimicrobial, and antioxidant effects. And now there might be one more.

Gut-brain communication

A recent preclinical study by scientists at the University of South Florida Health explored interactions between the gut microbiome and the brain. Emerging evidence had indicated that short-chain fatty acid metabolites produced by beneficial gut bacteria contribute to brain health. However, the abundance of such metabolites is often reduced in older people with mild cognitive impairment and Alzheimer’s disease, but a possible association remained largely unknown.

When these gut-derived microbial metabolites travel through the blood to the brain they bind to and activate the free fatty acid receptor 2, a cell signalling receptor expressed on brain cells called neurons with a hitherto unknown effect. One hallmark pathology of Alzheimer’s disease is hardened deposits of amyloid-beta protein that clump together between nerve cells to form amyloid protein plaques in the brain. This contributes to the neuron loss and death that ultimately cause the onset of Alzheimer’s, a neurodegenerative disease characterized by loss of memory, thinking skills and other cognitive abilities.

The research findings

In step one, the new study showed for the first time that the stimulation of the free fatty acid receptor 2 can be beneficial in protecting brain cells against toxic accumulation of the amyloid-beta protein associated with Alzheimer’s disease. By blocking the receptor the scientists found an abnormal build-up of the amyloid-beta protein proving the importance of functioning receptors for sustained brain health.

In step two, the scientists performed a large-scale virtual screening of 144,000 natural compounds to find other potential candidates that could stimulate the free fatty acid receptor 2 equally well compared to the microbial metabolites. Among the leading 15 compounds, the most potent in binding to and stimulating the receptor was fenchol.

In step three, further experiments in human neuronal cell cultures, as well as worm and mouse models of Alzheimer’s disease demonstrated that fenchol significantly reduced excess amyloid-beta accumulation and death of neurons by stimulating the free fatty acid receptor 2 signalling.

Still early days

Although the intriguing preclinical findings look promising it is still early days. Before you start throwing lots of extra basil into your salad to help prevent the development of dementia, be aware that much more research is needed including in humans. A key question is whether fenchol consumed in basil itself would be more or less effective than administering the compound in a pill.

And a final caveat, if you google fenchol you will find several websites covering cannabis in which it is also present. But I would stick to basil to enhance the taste of food as well as possibly preventing the development of dementia – or not.

Time for Ginger

We have so far produced around 200 blogs covering harmful or beneficial effects of food and food ingredients but none about the potential beneficial effects of ginger. So when a team from the University of Michigan published a story about 6-gingerol, the main bioactive compound in ginger root, and its beneficial effects on certain autoimmune diseases in mice, we decided that it was time for another good news story.

A caveat though, the Michigan Medicine research covered administration of pure 6-gingerol to mice affected by lupus, a disease which attacks the body’s own immune system, and an associated condition called antiphospholipid syndrome causing blood clots. The 6-gingerol prevented neutrophil extracellular trap release, which is triggered by the autoantibodies that these diseases produce.

If it sounds complicated, be reassured that we will rather focus on more general beneficial effects of consuming ginger.

The common use of ginger root

Ginger is a flowering plant whose rhizome, ginger root, is widely used as a spice and a folk medicine. It is actually one of the first spices to have been exported from Asia, arriving in Europe with the spice trade, and was used by ancient Greeks and Romans. It belongs to the same family as turmeric and cardamom.

Ginger has a firm, striated texture. The flesh of the ginger rhizome can be yellow, white or red in colour, depending on the variety. It is covered with a brownish skin that may either be thin if harvested young or thick after mature harvesting.

Ginger has long been perceived to have anti-inflammatory and antioxidative properties and has been used traditionally as a herbal medicine for the treatment of many ailments, including chronic conditions such as asthma and arthritis. The health-promoting properties of ginger have been attributed to its richness in phenolic phytochemicals, such as gingerols and shogaols. The most abundant in fresh ginger is 6-gingerol (used in pure form in the above mentioned research) with concentrations of up to 2 mg/g in the root.

The general benefits researchers have found

Two Spanish researchers reported that ginger appears to be highly effective against nausea in people undergoing certain types of surgery. It may also help chemotherapy-related nausea. However, it may be the most effective when it comes to pregnancy-related nausea and vomiting, such as morning sickness. According to their review of 12 studies that included a total of 1,278 pregnant women, 1–1.5 grams of ginger significantly reduced symptoms of nausea in particular and to some extent also vomiting.

Chronic indigestion is characterized by recurrent pain and discomfort in the upper part of the stomach. It’s believed that delayed emptying of the stomach is a major driver of indigestion. Interestingly, ginger has been shown to speed up emptying of the stomach.

In relation to its antiemetic properties, ginger acts peripherally, within the gastrointestinal tract, by increasing the gastric tone and motility due to anticholinenergic and antiserotonergic actions. This combination of functions explains the widely accepted ability of ginger to relieve symptoms of functional gastrointestinal disorders, such as dyspepsia, abdominal pain and nausea, which is often associated with decreased gastric motility.

Ginger has been an important ingredient in Asian medicine for centuries, particularly for pain relief in musculoskeletal diseases. In a meta-analysis of five studies involving 597 patients ginger proved to be moderately effective in reducing pain and disability caused by osteoarthritis, especially affecting the knee. Osteoarthritis is a common health problem. It involves degeneration of joints, leading to symptoms such as joint pain and stiffness.

Initial findings have shown that ginger may have powerful anti-diabetic properties. In a 2015 study of 41 participants with type 2 diabetes, 2 grams of ginger powder per day lowered fasting blood sugar by 12%. It also dramatically improved hemoglobin A1c (HbA1c), a marker for long-term blood sugar levels. HbA1c was reduced by 10% over a period of 12 weeks.

Sounds like ginger should have superfood status, but note that the number of trial participants have usually been low and the doses used and the frequency of administration have varied. A word of caution might be in place, but still worth a try.

Better use ginger in moderation

If you like consuming ginger and experience beneficial effects on your health, just be sure not to overdo it. It is clear that ginger is fine in small doses, but as usual everything in moderation. Some side effects have been reported in daily doses of more than 5 grams a day, which is a lot. They include gas, heartburn and an upset stomach.

Ginger tea doesn’t seem to have serious side effects. For one thing, it would be difficult to drink enough of the tea to be exposed to anything irritating or harmful. To exceed the 5 gram limit requires quite a few cups of tea a day.

High doses of ginger may help lower blood pressure but can in turn cause some lightheadedness as a side effect. Ginger also contains salicylates, the chemical in aspirin, that acts as a blood thinner. This can cause problems for people with bleeding disorders and could interact with blood thinner medication.

Although ginger has been used throughout the world for centuries as a therapeutic agent for pregnancy-induced nausea and vomiting, a word of caution is appropriate. The best available evidence suggests that ginger is a safe and effective treatment and that possible adverse events are generally mild and infrequent. However, there is still some uncertainty regarding the maximum safe dosage and the optimal duration of treatment. Both important areas for future research.

The bottom line

It is worth repeating that too much of anything – even something as natural as ginger – is bound to cause problems. But if you’re generally in good health and you like the zest that ginger provides, drink up and don’t worry.

Just be aware that due to the global COVID-19 pandemic, ginger prices across the world have soared.

ADDENDUM:

One of my readers affected by motion sickness pointed to the beneficial effects of consuming ginger to alleviate the symptoms. This has been documented by New York Times citing research published in Lancet involving 36 people highly susceptible to motion sickness. The subjects were given either two capsules of powdered ginger, an antinausea medication or a placebo, and 20 minutes later spun on a motorised chair for up to six minutes. Ginger delayed the onset of sickness about twice as long as the medication. Half the subjects who took ginger lasted the full six minutes, compared with none of those given the placebo or the medication.

A comprehensive review of the literature on motion sickness by the US Pharmacist provided further support of the beneficial effects of ginger.

Health benefits of pickled capers

If you like to spice your food with capers you may be in luck. Capers are the immature flower buds of the caper bush, Capparis spinosa, growing naturally in the Mediterranean and parts of Asia and Africa. Capers are harvested early in the morning before the heat opens the flower bud. There are also the caper berries, the resulting fruit picked much later in the season.

Archaeological evidence for human caper consumption dates back as far as 10,000 years, according to archaeological findings from Mesolithic soil deposits in Syria and late Stone Age cave dwellings in Greece and Israel.

Multiple health benefits proposed

Pickled capers are common in Mediterranean cuisine, where they provide a salty tang and decorative flair to a variety of meats, salads, pastas and other foods. Apart from the culinary benefits, capers may also have beneficial health effects. Too good to be true, read on and all will be revealed.

Actually, capers have traditionally been used as a folk medicine for hundreds if not thousands of years. True or false, it has been proposed that capers have anti-bacterial, anti-carcinogenic, analgesic, and anti-inflammatory properties. It has also been suggested that capers might strengthen capillaries and inhibits platelet clump formation in blood vessels, relieve rheumatic pain and act as an appetite stimulant. Sounds like a bit much. However, evidence for their efficacy is in some cases supported by clinical findings but as it is often purely anecdotal we need more proof.

Let’s untangle this a bit

It is well known that capers are rich in flavonoid compounds including rutin and quercetin. During the common pickling process of the capers, rutin is further converted to quercetin. This makes pickled capers the richest natural source of quercetin with reported maximum concentrations of 520 mg/100 g. Mechanistically, quercetin has been shown to exert antioxidant, anti-inflammatory, and anticancer activities in a number of cellular and animal models, as well as in humans through modulating the signalling pathways and gene expression involved in these processes.

And now new research from the University of California, Irvine School of Medicine has found that quercetin activates proteins required for normal human brain and heart activity. Specifically, the researchers discovered that quercetin modulates potassium ion channels in the KCNQ gene family. These channels are highly influential in human health and their dysfunction is linked to several common human diseases, including diabetes, cardiac arrhythmia, and epilepsy.

The study revealed that quercetin modulates the KCNQ channels by directly regulating how they sense electrical activity in the cell. In doing so, it tricks the channel into opening when it would normally be closed. Increasing the activity of KCNQ channels in different parts of the body is potentially highly beneficial, suggesting a previously unexpected mechanism for the therapeutic properties of capers.

Alternative sources of quercetin

So now we know that capers are actually good for our health. Capers are also low in calories and high in vitamins and minerals. Unfortunately, they are also high in salt thanks to the way they’re preserved. As they’re bitter on their own, capers are stored in brine or packed in salt. If you’re watching your salt intake that’s worth bearing in mind.

However, don’t despair as there are alternative sources of quercetin. It is found in many fruits, vegetables, leaves, seeds, and grains. Red onions and kale are common foods containing appreciable amounts of quercetin.

So you just have to dig in.

Red wine and/or exercise – your choice

Deteriorating brain function is the bane of getting old. The most severe and debilitating form of cognitive decline is the development of dementia, a collective term used to describe various symptoms of cognitive decline, such as forgetfulness. The estimated proportion of the general population aged 60 and over with dementia at a given time is between 5-8%.

Dementia is not a single disease in itself, but a general term to describe symptoms of impairment in memory, communication, and thinking. Although it mostly affects older people, it is not necessarily a normal part of ageing as it can be influenced by lifestyle factors.

Boosting brain function

Sure, a regular glass of red wine has been shown to have the ability to improve cognitive function as we age. We covered this in detail in a previous blog. But so does regular exercise. Exercise has a broad range of beneficial healthful effects.

A new study published on 9 July 2020 tested the hypothesis that it might be possible to reverse brain ageing through systemic interventions such as exercise. The scientists from the University of California tested whether the beneficial effects of exercise on cognition in aged mice could be transferred in plasma from one mouse to another. Indeed, plasma from young or old mice that had exercised when transferred to other aged mice showed beneficial effects in their brains even if they had not exercised.

How is this possible?

To discover what specific biological factors in the blood might be behind these effects, the amounts of different soluble proteins in the blood of active versus sedentary mice were measured. After some intensive search, the scientists identified the enzyme glycosylphosphatidylinositol-specific phospholipase D1 (Gpld1) as a factor in plasma that might mediate this favourable effect.

Gpld1 is produced by the liver. The team found that Gpld1 increases in the blood circulation of mice following exercise, and that Gpld1 levels correlate closely with improvements in the animals’ cognitive performance.

And not only in rats!

Analysis of previously collected human data showed that Gpld1 is also elevated in the blood of healthy, active elderly adults compared to less active elders.

To test whether Gpld1 itself could drive the observed benefits of exercise, the researchers used genetic engineering to coax the livers of aged mice to produce extra Gpld1, and measured various aspects of cognition and memory. They found that three weeks of the treatment produced similar beneficial cognitive effects as six weeks of regular exercise.

The scientists are now working to better understand precisely how Gpld1 interacts with other biochemical signalling systems to produce its brain-boosting effects (as it doesn’t pass the blood/brain barrier). The hope is to be able to identify specific targets for a future food supplement with Gpld1 that could one day confer many of the protective benefits of exercise for the frail.

So what’s your choice?

So now there is a choice, red wine or exercise or maybe both to retain good cognitive function.

But the question is how much exercise is needed to get the optimal benefit. Would the recommended 10,000 steps a day be sufficient and would a glass of red wine add to the benefit?

Or, horror, would the liver be too busy to metabolise the alcohol from the red wine to have time to also produce the Gpld1?

I want to know more!

Alcohol and brain function in old age

Let’s get this out of the way at the start. It is clear that alcohol misuse is a leading cause of morbidity and mortality. As an example, binge drinking has been shown to lead to a higher risk of cardiovascular disease.

But what about lower level alcohol consumption?

Some previous studies have reported that low to moderate alcohol consumption show benefits to cognitive function. However, others have found no, minimal, or even adverse effects associated with alcohol consumption.

So what to believe?

Association studies are difficult to interpret correctly as most effects studied are multifactorial and vary over time. In particular, a one time measurement can easily be misleading as the time factor is disregarded.

To overcome this challenge, a study published in June 2020 by researchers from the University of Georgia used repeated measurements of health and lifestyle, including questions on drinking habits, in a group of almost 20,000 middle-aged and older participants over a ten-year period.

The participants had their cognitive function measured in a series of tests looking at their overall mental status, word recall and vocabulary. The test results were combined to form a total cognitive score.

And the good news – light to moderate drinking may preserve brain function in older age.

Compared to nondrinkers, those who had a drink or two a day tended to perform better on cognitive tests over time. The optimal amount of drinks per week was between 10 and 14 drinks.

Even when other important factors known to impact cognition such as age, smoking or education level were controlled for, they saw a pattern of light drinking associated with better cognitive function.

The debate will continue

The debate is clearly not over about potential benefits of moderate alcohol consumption. We have written about the balance of the good and bad of alcohol consumption before.

For a while it looked like the fact that regular, moderate alcohol consumption had been shown to promote heart health was settled. And then came another review of previously published research questioning this conclusion.

Several studies pointed to similar protective benefits of moderate alcohol consumption for brain health. And then a systematic review of existing literature on alcohol consumption concluded that there seemed to be no safe level of drinking alcohol.

Believe what you will, but at my age I will cling to the latest findings as it seems to be a solid design of the study.

The benefits of red onions

During the current doom and gloom we need to be cheered up with some positive news. And should you read this when a vaccine has disarmed the coronavirus causing the COVID-19 pandemic in 2020 and governments around the world have taken the necessary actions to limit global warming to 1.5ºC, well, you might still appreciate some good news. 

So here goes.

Multiple health benefits

The next time you go shopping you might reach for red onions. Onions belong to the Allium family of plants, which also includes chives, garlic, and leeks. Farmers have cultivated Allium vegetables for millennia. These vegetables have characteristic pungent flavours and some beneficial medicinal properties. The benefits among many include a reduction of the risk of several types of cancer, improving mood, and maintaining skin and hair health.

Looking back in time, ancient medical texts from Egypt, Greece, Rome, China, and India all cite therapeutic applications for Allium vegetables.

Contemporary studies confirm the early findings. One review from 2015 found a general relationship between an increased consumption of Allium vegetables and a reduced risk of cancer, especially cancers of the stomach and gastrointestinal tract.

Such a relationship was further supported by a 2019 Chinese study that compared 833 people with colorectal cancer with 833 people who did not have the disease. The researchers found that the risk of colorectal cancer was 79% lower in those who regularly consumed Allium vegetables, such as onions.

Experts do not fully understand the exact mechanism by which some compounds in onions inhibit cancer. There are compounds called organosulfurs in onions, some of which have been shown to suppress aspects of tumour growth. However, further research is necessary to confirm which compounds in onion have protective effects against cancer.

But there is more

A wide range of further beneficial effects have also been proven. Different biological properties, such as antioxidant, antimicrobial and anti-diabetic activities, have been reported.

Not surprising as onions are nutrient-dense. One medium onion has just 44 calories but delivers a considerable dose of vitamins, minerals and fibre.

As a good source of vitamin C, onions may support the building and maintenance of collagen. Collagen provides structure to skin and hair.

A 2014 review found that among various activities of Allium vegetables, regulation of hypoglycaemic activity is considered important in helping to control diabetes. Sulfur compounds including S-methylcysteine and flavonoids such as quercetin are mainly responsible for the hypoglycaemic activity. S-methylcysteine and flavonoids help to decrease the levels of blood glucose, serum lipids, oxidative stress and lipid peroxidation, as well as increasing antioxidant enzyme activity and insulin secretion. 

A 2019 review found that quercetin, a compound in onion skin, had links to lower blood pressure when the researchers extracted it and administered it as a supplement.

Somewhat surprisingly onions have been shown to be able to fight potentially dangerous bacteria, such as Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus and Bacillus cereus.

Onions are also rich in B vitamins, including folate (B9) and pyridoxine (B6) playing key roles in metabolism, red blood cell production and nerve function.

Lastly, they’re a good source of potassium, a mineral in which many people are lacking.

I hope you’re convinced by now.

So why red onions?

Any Allium vegetable would do but there is something special with the red colour of red onions.

A Canadian study revealed that the red onion not only has high levels of quercetin, but also high amounts of anthocyanin, which enriches the scavenging properties of quercetin molecules. Anthocyanin is instrumental in providing colour to fruits and vegetables so it makes sense that the red onions, which are darkest in colour, would have the most cancer-fighting power.

There are plenty more benefits associated with Allium vegetables, but this is it for now as I’m off to buy some red onions.

Not all “bad” cholesterol is equally bad

Cholesterol is essential for all animal life with a typical adult human body containing about 35 g. It is an essential structural component of animal cell membranes and a precursor molecule for all steroid hormones and vitamin D. About one gram is synthesised by the cells of the body per day, while some is excreted through the liver.

Cholesterol is transported in blood bound to proteins called lipoproteins. There are two types of lipoproteins – low-density lipoproteins or LDL and high-density lipoproteins or HDL. Cholesterol bound to LDLs is often called the bad cholesterol and when bound to HDLs the good cholesterol.

Most of us know that high levels of LDL cholesterol can narrow the insides of blood vessels by forming plaques on their walls, thus restricting blood flow. This increases the risk of heart disease and stroke. HDL on the other hand carries the cholesterol to the liver. The liver then flushes it from the body, thus decreasing the risk for heart disease and stroke.

Sounds simple enough? Sorry, time to think again as it is more complicated than that.

Different subclasses of LDL

Contrary to normal wisdom, it has been shown that about 75 percent of patients who suffer heart attacks have total LDL levels that give no indication of cardiovascular risk. What’s going on?

Well, let’s complicate things a little bit.

It has been known since the early 1950s that LDLs comprise of three major subclasses, with particles of different sizes and densities. Subclass A contains more of the larger and less dense LDL particles; subclass I comprises an intermediate group; and finally, subclass B with smaller and denser LDL particles.

It has previously been shown that small and dense LDL is strongly associated with increased cardiovascular risk.

Now new research studying the molecular effect of the different LDL subclasses on blood vessel endothelium has confirmed that of the three subclasses that comprise LDL, only one causes significant damage. LDL subclass B was found to be the most damaging to endothelial function and contributed the most to the development of plaques. Therefore, it’s not the total amount of LDL cholesterol, but rather the concentration of subclass B to the other two, subclass A and subclass I, that should be used to diagnose the risk of heart attack.

However, don’t worry too much about the LDL subclasses as they are more of a diagnostic tool at this time.

Reasons for high levels of bad cholesterol

Let’s make clear from the beginning that most of our circulating cholesterol is actually formed by our own body and genetically determined. So we can blame our parents. However, environmental factors, in particular diet and exercise, appear to also be able to influence the expression of LDL subclasses. 

It was once thought that eating too much of cholesterol-rich foods (such as eggs) was the main cause of high cholesterol. Sure, some foods are high in cholesterol, but indulging in such foods has little influence on our blood levels of cholesterol as such.

Although typical daily cholesterol dietary intake might be around 300 mg, most ingested cholesterol is esterified and poorly absorbed by the gut. The body also compensates for absorption of ingested cholesterol by reducing its own cholesterol synthesis. For these reasons, cholesterol in food has little, if any, effect on long-term concentrations of cholesterol in the blood.

On the other hand, eating too much of foods high in saturated fats is more of a problem, and this has more impact on blood cholesterol levels. The principle mechanism by which saturated fat intake can influence LDL cholesterol is via decreased LDL receptor activity, which in turn decreases liver clearance and excretion of LDL cholesterol.

Mono- or poly-unsaturated fats have the opposite effect, increasing LDL receptor activity and turn-over of LDL cholesterol.

So what can you do?

People with high levels of LDL cholesterol may thus be able to reduce their cholesterol levels by:

• Limiting foods that have a high saturated fat content (such as many biscuits, cakes and fatty take-away foods)
• Replacing saturated fats in the diet with mono- or poly-unsaturated fats found in nuts, avocados and oily fish

It is also useful to include more fibre-rich foods in the diet such as fruit, vegetables and wholegrain bread and cereals.

Remember to keep active as it is also an important part of keeping cholesterol levels healthy.

Eating foods enriched with plant sterols has been proven to lower cholesterol levels by up to 10 percent.

Equally, cholesterol-lowering medication has a similar effect and might be necessary if lifestyle changes are not sufficient to reach a desirable cholesterol level. Statin drugs targets the first 18 steps of a complex 37-step process in the formation of cholesterol.