A teaspoon of horseradish

Horseradish

Horseradish another superfood if you believe there are such foods.

Here we go again, another superfood. This time with cancer fighting properties. And the scientists say that a teaspoon is enough to achieve the beneficial effects. So what’s not to like?

Well, the pungent aroma and the bitter taste of the food in the first place. We are talking about glucosinolates found in a range of cruciferous vegetables, but in horseradish in particular.

And when the glucosinolates are activated some of the resulting compounds have proven to be protective against cancer. And that we like.

A bit of background

Glucosinolates are natural components of many pungent plants such as mustard, broccoli, cabbage, and yes horseradish. About 132 different glucosinolates are known to occur naturally in plants. As is common, these natural chemicals contribute to a plant’s defence against pests and diseases.

The pungent taste of those plants is due to mustard oils produced from glucosinolates when the plant material is chewed, cut, or otherwise damaged. The plants contain the enzyme myrosinase that is released during chewing and transforms the glucosinolate into mainly isothiocyanate (mustard oil), the active form. The myrosinase and glucosinolates are stored in separate compartments of the plant cells so not to damage the plant itself until chewed.

Glucosinolate type and quantity vary depending on the plant variety, although closely related taxonomic groups typically contain only a small number of the different compounds. Many reviews have addressed the occurrence of some glucosinolates in vegetables with a major focus on negative aspects, like antinutritional or goitrogenic effects. However, there is a positive side now getting increased attention represented by beneficial health properties of some other glucosinolates.

So what are the health benefits?

The metabolic activation of glucosinolates results in the formation of isothiocyanates that in turn have been found to inhibit the development of cancer in several organs in rats and mice, including the bladder, breast, colon, liver, lung, and stomach. Also human epidemiological studies suggest that isothiocyanates are protective against cancers of the lungs and alimentary tract. Studies in animals and experiments with cells grown in the laboratory have identified several potential ways in which these compounds may help prevent cancer by:

  • protecting cells from DNA damage
  • inactivating carcinogens
  • having antiviral and antibacterial effects
  • having anti-inflammatory effects
  • inducing cell death (apoptosis)
  • inhibiting tumor blood vessel formation and tumor metastases.

And now a research team has studied the effects of the glucosinolates present in horseradish. The researchers found different concentrations of allyl isothiocyanate (AITC) and  1-cyano 2,3-epithiopropane (CETP) depending on the horseradish variety. And AITC is the one you want. The team suggests that AITC is a good dietary anti-carcinogen, not only because it activates the enzyme responsible for detoxifying cancer-causing molecules, but also because a large proportion of it, 90%, is absorbed when ingested.

Getting sufficient protection

horseradish-prepared

A teaspoon of horseradish is beneficial to health.

Eating 3–4 portions of broccoli per week has previously been shown to provide a protective effects against certain cancers.

And now the researchers showed that horseradish contains approximately 10 times more glucosinolates than its superfood cousin, broccoli.

So your choice. You can eat 3-4 teaspoons of horseradish a week if you can stomach it, or you can replace each teaspoon by a portion of broccoli if that is more appetising. Or a range of other cruciferous vegetables.

Scientific knowledge vs. consumer experience

Disparate views between
scientists and consumers
(Drawing: Robin Hutton)

Scientists have long recommended that we eat at least 400g of fruit and vegetables a day with some countries going even further. Australia recommends a daily intake of two fruit and five vegetable portions equivalent to 750g. But the experience of consumers is that this is almost impossible and anyway could be quite expensive depending on seasonality and regional availability.

Many scientists believe that genetically modified agricultural commodities will solve future food shortages following an increasing world population and harsher growing conditions due to global warming. The public is sceptical having experienced previous backlashes. Monocultures are expected to threaten species versatility and superweeds to overwhelm production systems.

Scientists warn about an ‘obesity epidemic’ that will overwhelm the future hospital system and issue nutrition recommendations. The general public experiences an increasingly busy lifestyle with work pressure inundating leisure time. There is little time for food preparation and a living environment conducive of exercise is missing.

What to do?

These are some of the topics discussed in a just released rather unique book that combine the views of sociological and public health expertise to provide a holistic discussion of food safety issues.

The book offers a comprehensive understanding of the current scientific knowledge concerning risks associated with food production, processing and consumption, with particular attention to the gap between scientific research and public perception.

The book is thematically arranged according to the application of theoretical approaches in sociological theory – the socio-cultural perspective, the risk society perspective and the governmentality perspective – each chapter focuses on a particular area of interest or concern in relation to food, for example:

  • the ‘obesity epidemic’,
  • the benefits or otherwise of dietary supplements,
  • caffeine consumption,
  • GM food,
  • alcohol,
  • organic food,
  • the consumption of fruit and vegetables, and
  • pathogens and contaminants.

The existing literature is covered in detail and the book offers illustrative empirical examples, whilst identifying gaps in knowledge and areas for further research.

Interested?

The book is available now from Routledge:

Risk book

 

 

 

 

 

 

Food and the Risk Society
The Power of Risk Perception
By Charlotte Fabiansson, Stefan Fabiansson

ISBN 978-1-472-47896-2
© 2016 – Routledge

282 pages

Eating in moderation

Pizza size is all in the eye of the beholder (Photo: Valerio Capello).

Pizza size is all in the eye of the beholder (Photo: Valerio Capello).

In 1978, I visited the USA with two colleagues on a mission to study meat quality. After travelling by car for many hours to reach Texas we got very hungry and stopped at a pizza joint in Oklahoma. We had a choice of small, medium, large and very large pizzas. We settled on one medium each as one should eat in moderation, but huge pizzas each covering half of the table arrived. We couldn’t even eat half of the pizzas.

This highlights that there is no universal measure of eating in moderation.

What is moderation?

Eating in moderation seems to be practical advice for a healthy diet, but a new study suggests that it is an ineffective guide for losing or maintaining weight. The scientists found that the more people liked a food, the more flexible their definitions of moderation were. And who doesn’t like pizza?

Of course moderation is a relative term that doesn’t allow a clear, concise way to guide behaviour as people think of moderation through their own objective lens. They tend to exaggerate what moderation is based on individual perceptions. Frugal Scandinavians might see a five-slice pizza as a satisfying amount, while more generous Americans might desire a ten-slice pizza.

The scientists concluded that people do think of moderation as less than overeating, so it does suggest less consumption. But unfortunately they do think of it as more than what they should eat. So moderation is more forgiving of their desires. The study adds to the growing body of knowledge that suggests people are poor judges of the amounts of food they eat.

In a general backlash against dieting there are now entire healthy eating movements oriented toward the idea of moderation. But those movements assume people can actually be good judges of what they’re eating and what constitutes an appropriate amount, which they obviously are not.

So what to do?

Go for a smaller plate to reduce food intake.

Go for a smaller plate to reduce food intake and still be happy.

A recent Cochrane review of 69 food consumption intervention studies, published between 1978 and 2013, found that people consistently consumed more food and drink when offered larger-sized portions, packages or tableware than when offered smaller-sized versions. This is a little confusing and the researchers stated that the mechanisms underlying the “portion size effect” are not fully understood.

However, people generally perceive the amount served to them as representing an appropriate portion size and consume less when offered smaller portions and more when offered larger portions. The way in which food and drink is presented can also influence consumption. The size and shape of a plate or glass can alter perceptions of quantity and influence how much is consumed.

I repeat, the size of your plate seems to be important in how much you eat. And the size of your glass may influence how much you drink.

In support of this theory another study proved that a larger glass of wine — not the amount in the glass, but the size of the glass itself — might make you drink more. Researchers tracked purchases in a bar over 16 weeks, during which time different sizes of wine glasses were used, small (250 mL), standard (300 mL) or large (370 mL), while the serving of wine was kept at 175 mL. With larger glasses there was an almost 10% increase in wine consumption. It may be that larger glasses change our perceptions of the amount of wine, leading us to drink faster and order more.

Go for smaller tableware

Although it seems natural to eat less with reductions in the portion size presented, it is very interesting to notice the influence of the size of glasses and plates. The solution to overindulgence might be to reduce the size of your tableware. That could be quite helpful and easy to fix at home.

New bad findings for bisphenol A

Canned food

Bisphenol A can be found in many canned food products.

We have covered bisphenol A, called BPA for short, several times before. In case you need to be reminded, it is a chemical widely used in plastic water bottles, metal food cans, and receipt paper. A large number of scientific publications have questioned the safety of BPA. High doses were found to influence the hormonal balance by acting as an endocrine disruptor with oestrogenic effects already in the 1930’s.

Debate over the toxicity of BPA is on-going with findings of potential low-dose effects particularly worrying. The European Food Safety Authority (EFSA) has so far refrained from suggesting that BPA should be banned, contrary to the opinion of government scientists from France and Denmark. At least EFSA lowered the temporary tolerable daily intake (tTDI) by more than 10 times in its latest opinion. And BPA has been removed from baby bottles in many countries.

New bad reports piling up

By setting a temporary TDI, EFSA committed to the re-evaluation of BPA when a two-year study by the U.S. National Toxicology Program becomes available in 2017. But in the meantime results from several other studies have been published.

A report by the Dutch National Institute for Public Health and the Environment (RIVM), critically examined two studies describing pre- and perinatal effects of BPA on the immune system. The report recommended supporting research on alternatives to BPA and advising consumers to reduce their exposure to BPA from food and other sources.

Third

Foetal exposure to BPA promotes obesity later in life for girls.

And another recent study equally points to the often neglected prenatal exposure to BPA. A team of U.S. researchers tracked 369 mother-child pairs from the third trimester of pregnancy until the children turned seven years old. They measured BPA levels in the mothers’ urine during pregnancy and then checked the children’s height, weight, waist circumference, and body fat as they aged, also measuring their BPA levels. They adjusted the results for factors that could potentially skew the results, including race and pre-pregnancy obesity among the mothers.

They found that the higher the mothers’ BPA exposure was during pregnancy, the more signs of obesity girls showed at age seven. There was no such association for boys; nor was there any relation between BPA levels in the children’s urine and obesity as they grew.

So it seems that the foetal period is when we’re most vulnerable to BPA and its ability to alter metabolism and the way our bodies generate fat cells. It is not surprising that BPA seems to affect girls differently than boys since as an endocrine-disrupting chemical it mimics or blocks hormones produced by the body. Boys and girls produce different hormones, so hormone-disrupting chemicals might be expected to affect them differently.

And if that’s not enough, experimental laboratory evidence suggests that BPA is a neurodevelopmental toxicant. In further disturbing findings, a longitudinal cohort study confirmed the association between prenatal BPA exposure and child behaviour in preschool-age children, accounting for postnatal BPA and other potential confounders. Among boys, prenatal BPA exposure was positively associated with higher scores on all syndromes and significantly associated with Emotionally Reactive and Aggressive Behaviour. Inverse associations were seen in girls for all syndromes and these associations were significant for Anxious/Depressed and Aggressive Behaviour.

How long to wait?

Protect your child from becoming obese.

Take your own action to protect your child from becoming obese.

So it seems pretty clear that BPA can have significant effects at levels of exposure seen in real life.

Do we really have to wait further for some real progress. Authorities seem reluctant to take decisive action despite overwhelming proof of harmful effects. Sure, not all findings point in the same direction and alternatives to BPA might be as bad.

But don’t despair, you can take your own action. To reduce exposure to BPA, the National Institute of Environmental Health Sciences recommends avoiding plastic containers numbers 3 and 7, shifting from canned foods to fresh or frozen foods, and, when possible, choosing glass, porcelain, or stainless steel containers, especially for hot food and liquids.

Related articles

Hot potato

Not again! This time it is the simple potato that’s being demonised. This seems to never end in that scientists pick one food after another and try to find a bad apple in a complex diet. Sorry, so far there are no adverse effects reported for apples, but you just wait. Probably just a matter of time.

And the statistics used become more and more elaborate making it impossible to penetrate the reported findings. All based on dubious food frequency questionnaires in the first place.

So what’s new?

Scientists demonise potatoes.

Scientists demonise potatoes for causing hypertension.

I have to give it to them that the researchers of the new report used an impressive number of people, overall over 187,000 men and women from three large US studies covering more than 20 years of follow-up. They all belonged to a cohort of health professionals, the same groups that have been used previously to report potential public health impacts of a range of different foods.

Unfortunately, the major shortcoming of all those reports is their dependence on food frequency questionnaires to capture dietary intake details.

In this case they analysed consumption of 130 foods and beverages, including the frequency of potato consumption. This might be fine for common foods, but what about all other minor foods we eat less regularly? If they aren’t captured you have no idea of their influence. Also you need a pretty good memory to recall all you ate during the past year.

Try it yourself. How often did you consume apples or ice cream? It will be more of a guesstimate and you might not even want to admit that you ate ice cream three times a week.

And also they asked participants to self report if they had been affected by hypertension as diagnosed by a health professional since their hypothesis was that eating a lot of potatoes would lead to an increase in blood pressure.

And the findings?

The researchers predictably found that higher intakes of boiled, baked, or mashed potatoes, and French fries were associated with an increased risk of developing high blood pressure. But now it gets more confusing.

After taking account of several other risk factors for hypertension, the researchers found that four or more servings a week of baked, boiled, or mashed potatoes was associated with an increased risk of hypertension compared with less than one serving a month in women, but not in men.

But higher consumption of French fries was associated with an increased risk of hypertension in both women and men.

And even more confusing, consumption of potato crisps (chips if you’re American) was associated with no increased risk.

And finally, replacing one serving a day of baked, boiled, or mashed potatoes with one serving a day of a non-starchy vegetable was associated with a lowered risk of developing hypertension.

So what to believe?

Should potatoes be included in the vegetable group?

Should potatoes be included among other vegetables or not, who can say?

First the main rationale of the study. Potatoes are one of the world’s most commonly consumed foods – and have recently been included as vegetables in the US government healthy meals programs, due to their high potassium content. Not everyone agrees to this move. So the researchers set out to determine whether higher long term intake of potatoes could be linked to incident hypertension.

And they say their findings have potentially important public health ramifications, as they do not support a potential benefit from the inclusion of potatoes as vegetables in government food programs. Instead the findings support a harmful effect that is consistent with adverse effects of high carbohydrate intakes seen in controlled feeding studies.

But if you noticed that replacing a serving of potato with non-starchy vegetables lowered the risk of hypertension, the findings could actually be related to reduced vegetable consumption when consuming a lot of potatoes. Nitrate in vegetables is transformed to nitric oxide in the body. And nitric oxide is a vasodilator that reduce blood pressure.

Critics of the study

I am not the only critic of the study. In a linked editorial, other researchers argued that, although diet has an important part to play in prevention and early management of hypertension, dietary behaviour and patterns of consumption are complex and difficult to measure. Prospective cohort studies that examine associations between various dietary patterns and risk of disease provide more useful insights for both policy makers and practitioners than does a focus on individual foods or nutrients.

To be fair also the researchers acknowledge some study limitations and said that, as with any observational study, no firm conclusions can be drawn about cause and effect. But that didn’t deter the popular press to latch onto the findings, there are plenty of potato consumers to scare.

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Dark chocolate’s beneficial deeds

Only dark chocolate is beneficial to health (Photo: André Karwath)

There are several different varieties of chocolate (Photo: André Karwath)

Having dealt with hazards in food during a lifetime, it is always nice to be able to look at the benefit side. We all need good news stories. However, even good news stories can be deceptive. There is much fuss made over what is called superfoods, while the overall diet is more important. And scientists test individual food components in isolation reporting highly beneficial effects in unrealistic animal experiments that have no relevance to real life. Resveratrol that can be found in red wine is supposed to be heart protective, but will require daily consumption of many bottles of wine to reach an effective dose.

But dark chocolate seems to be the real thing with normal consumption amounts sufficient to be beneficial to health.

Not all chocolates are the same

Chocolate is made from cocoa solids (cacao), mixed with fat (cocoa butter) and finely powdered sugar to produce a solid confectionery. There are several types of chocolate, dark, milk and white, classified according to the proportion of cocoa solids used in a particular formulation.

Dark chocolate, also known as “bittersweet” or “semisweet” chocolate, contains little or no added sugar, but plenty of antioxidant flavonoids that contribute to the dark colour. More flavonoids means darker chocolate.

Dark chocolate has already been hailed for its positive effects on cardiovascular health and can help lower blood pressure.

Milk chocolate is not a good antioxidant source as milk binds to antioxidants in chocolate making them unavailable.

White chocolate contains no cocoa solids at all and therefore is not a good source of antioxidants.

Let’s look at the details

Nitric oxide reduces blood pressure.

Dark chocolate increases the effect of nitric oxide in reducing blood pressure.

It is widely known that dietary nitrate leads to the substantial elevation of circulating nitrite, which is subsequently converted into bioactive nitric oxide. Bioactive nitric oxide relaxes blood vessels, increases glucose uptake and regulate muscular contraction. Dietary supplementation with nitrate rich beetroot juice has become increasingly popular in athletes and has consistently been shown to reduce oxygen demands during submaximal exercise allowing athletes to go further for longer.

Dark chocolate works a little differently. Cocoa beans contain a substance called epicatechin, a flavanol that releases vasoactive components from the endothelial cells in blood vessels increasing the bioavailability of nitric oxide. The increased bioavailability and activity of nitric oxide dilate blood vessels and increases blood flow, resulting in a reduction of blood pressure. Previous research have shown that as little as 6g per day can reduce mild hypertension, while around 40g per day can increase blood flow also in healthy patients.

Providing an edge

The previous findings have now been confirmed in a study undertaken at London’s Kingston University The scientists found that the tasty treat could help give sports enthusiasts an extra edge in their fitness training. They used a group of nine amateur cyclists. After undergoing initial fitness tests to establish a baseline for comparison, the participants were split into two groups. The first group was asked to replace one of its normal daily snacks with 40g of a dark chocolate for a fortnight, while the other participants substituted 40g of white chocolate for one of their daily snacks as a control.

The effects of the athletes’ daily chocolate consumption were then measured in a series of cycling exercise tests. The cyclists’ heart rates and oxygen consumption levels were measured during moderate exercise and in time trials. After a seven-day interval, the groups then switched chocolate types and the two-week trial and subsequent exercise tests were repeated.

After eating dark chocolate, the riders used less oxygen when cycling at a moderate pace and also covered more distance in a two-minute flat-out time trial.

All good news.

Benefits confirmed by EFSA

Only dark chocolate is beneficial to health (Photo: Simon A. Eugster)

Only dark chocolate is beneficial to health (Photo: Simon A. Eugster)

And the beneficial effects have been confirmed by the European Food Safety Authority.

The Belgian chocolate manufacturer, Barry Callebaut, has exclusive use of an existing authorised claim stating that cocoa flavanols “help maintain the elasticity of blood vessels, which contributes to normal blood flow”. The authorised conditions of use require the product label to state that 200mg of cocoa flavanols are needed for the beneficial effect. The current claim can only be used for cocoa beverages with cocoa powder or for dark chocolate which provides at least a daily intake of 200mg of cocoa flavanols.

There has been concern that authorising claims on products such as chocolate could encourage over-consumption. However, the EFSA Opinion states that the amount required for the effect can be eaten within the context of a balanced diet.

So as long as you keep within your normal calorie intake level, feel no guilt when indulging in some dark chocolate.

Mould on your food

artisan_bakery

What to do with artisan bread going mouldy?

You’ve bought a fancy artisan wholemeal bread made from only natural ingredients, no preservatives it proudly states. It was expensive so you only eat half of the bread, saving the rest for another day. It was wonderful. Two days later when you intend to eat the other half it is all mouldy.

In poorer circumstances there is no option but eat what is on offer. But in an affluent society we have the option to throw it out, even if it hurts as it was so nice.  Or you could attempt to rescue the unaffected part.

What to do?

Let’s look at the facts

Moulds belong to a large and taxonomically diverse range of fungal species that characteristically grow hyphae. The hyphae are generally transparent, so they appear like very fine, fluffy white threads over the surface, especially on food. We have tamed some moulds to become beneficial, others cause food spoilage, and yet others are seriously harmful to human health.

On the beneficial side, the most well-known mould product is penicillin produced by the Penicillium mould and used as an antibiotic to kill bacteria. Moulds are also essential components in the manufacturing of several food products, such as some cheeses, sausages and soy sauce.

On the harmful side, several moulds produce compounds toxic to animals and humans called mycotoxins. The worldwide contamination of food and feed with mycotoxins is a significant problem. According to the Food and Agriculture Organisation of the United Nation 25% of the world’s crop harvests are contaminated with mycotoxins. There are currently more than 400 known mycotoxins.

Where to find mycotoxins?

mouldy_fruit

Moulds can grow on many different types of food.

Mycotoxins can occur in a wide range of different foodstuffs. These include cereal-based products – such as bread, breakfast cereals, pasta, pastries, biscuits and snacks – groundnuts (peanuts), tree nuts, oilseeds, dried fruits, spices, coffee, wine, apple juice and milk. Mycotoxins are typically highly resistant to temperature and processing, so destruction during conventional food production does not occur.

The mycotoxins of most concern from a food safety perspective include the aflatoxins (B1, B2, G1, G2 and M1), ochratoxin A, patulin and toxins produced by Fusarium moulds, including fumonisins (B1, B2 and B3), trichothecenes (mainly nivalenol, deoxynivalenol, T-2 and HT-2 toxin) and zearalenone.

A threat to health

Mycotoxins can cause a variety of acute and chronic adverse health effects.

  • Aflatoxins, and in particular aflatoxin B1, are genotoxic and carcinogenic, and can cause liver cancer in humans.
  • Ochratoxin A causes a number of toxic effects in animal species. The most sensitive and notable effect is kidney damage. It may also have effects on foetal development and on the immune system.
  • Patulin has been shown to have various toxic effects and can harm the immune system and gastrointestinal tract.
  • Fumonisins have been related to oesophageal cancer in humans, and to liver and kidney toxicity in animals.
  • Trichothecenes can be acutely toxic to humans, causing sickness and diarrhoea, but at much higher levels than those typically present in food. Reported chronic effects in animals include suppression of the immune system.
  • Zearalenone is oestrogenic and has been shown to exhibit hormonal effects, such as infertility, particularly in pigs.

What to do with the mouldy food?

All of us have observed mould growth on food – be it on the piece of bread above or on a plum left sitting on the kitchen counter for an extended period of time. But you have no idea if this is a mycotoxin-producing mould harmful to health or just an annoyance spoiling the food.

There is a simple rule of thumb. For firm foods cut off the piece affected by the mould and eat the rest, while mouldy soft foods should be discarded.

Hard cheeses are good examples of firm foods that can be rescued. Moulds need moisture to grow and in dry cheeses like cheddar and parmesan there is not enough moisture for the mould to penetrate beyond the surface. Thus it is fine to remove a two centimeter piece of the cheese around the mould avoiding to cut into the mould.

Similarly, firm fruits and vegetables (such as cabbage, bell peppers and carrots) are fine to eat after removal of the mould.

And by all means remember that for some foods, like certain soft cheeses and processed meats, mould growth is part of the manufacturing process and they are perfectly fine.

On the other hand, mould on the surface of fluid foods such as yoghurt usually means that its mass of thread-like filaments have penetrated the item. Better discard the lot.

But how about our artisan bread, it is fairly dry but not really hard? This case is a little trickier. It might be sufficient to remove a solitary mould and eat the rest of the bread. However, with more extended mould growth the risk is higher. It might pay off to throw away the lot.

A final word of warning

pollution(Eric_Huybrechts)

Global warming will support further mould growth (Photo: Eric Huybrechts)

It is generally acknowledged that aflatoxins are genotoxic carcinogens. As a matter of fact they are amongst the most potent mutagenic and carcinogenic substances known.

A number of epidemiological studies have shown clear associations between aflatoxin exposure and incidence of liver cancer in areas with high prevalence of chronic hepatitis B, which is itself a risk factor for liver cancer.

Unfortunately, global warming will exacerbate the situation as mycotoxins occur more frequently in hot and humid climates favouring the growth of moulds.

The future might be bleak unless action is taken now to curb greenhouse gas emissions.

Too much fat or too much sugar

Added sugar cause more problem than high fat (Photo: Health Gauge)

Replacing fat with sugar is a bad choice (Photo: Health Gauge).

New research findings justifies another look at this topic we have covered before, but this is not easy with very polarised views. It used to be simple in the past. What’s now considered flawed research stated that fat, particularly saturated fat, was bad for our health. It increased cholesterol levels and caused heart disease with early death. Low-fat diets were in vogue and industry produced plenty of low-fat alternatives for the proselytes.

Unfortunately, industry substituted fat with sugar and that didn’t help the situation much. Actually, it now seems to have made what was considered a bad situation even worse.

Fight between old and new science

In a previous blog I put my toe into the sugar debate, an issue that has recently turned nutrition on its head. Now overindulgence in sugar is the culprit behind several diseases and increased mortality. So in the one corner we have the old die-hard supporters of the low-fat diet, while in the other corner we have the fresh newcomers daring to promote a low-carb high-fat diet.

Although the low-fat supporters have lost considerable ground the umpire seems to still be sitting on the fence. The 2015-2020 Dietary Guidelines for Americans target both saturated fats and added sugars as nutrients to limit and seem to give them equal weight in their advice:

  • Consume less than 10% of calories per day from added sugars, and also
  • Consume less than 10% of calories per day from saturated fats.

Let’s just pause for a moment to consider this new advice. The energy stored in our food is measured in terms of calories. Technically, one calorie is the amount of energy required to raise the temperature of 1 gram of water 1º Celsius. However, in the food area a calorie is actually 1000 technical calories. Although the technical calorie unit is part of the metric system, it has been superseded in the International System of Units by the joule and used in some countries as the new energy measure. A food calorie is approximately 4.2 kilojoules. Confused, I thought so. So for convenience let’s stick to the common use of calorie in the food area and forget that technically it is actually kilocalories.

Now to be clear, sugar contains less than 4 calories, whilst fat contains 9 calories per gram. Thus, according to the above recommendations you could consume double the amount of added sugar compared to saturated fat to keep within the given proportion of energy allocated to each of the two nutrients. So although the recommendation looks evenhanded in reality it is not.

New studies support the low-carb camp

New scientific findings

New scientific findings give further support to the low-carb camp.

Back to the science. With the tables turning, low-fat diets are out and high-fat diets are very much in. Since the eat-less-saturated-fat advice has been around for decades, there should be proof around either way you would think. However, it took quite some time to disprove the fat hypothesis since it was considered heresy.

This has changed and a new article cites several meta-analyses of randomised controlled trials that did not find a connection between saturated fats and heart disease or overall death rates.

But it goes further with low-carb comparisons. A recent study suggested that low-fat diets might not be the way to go after placing about 150 adults on either a low-carb or a low-fat diet for a year. Participants on the low-carb diet lost more weight and lowered their risk for heart disease more than participants who followed a low-fat diet.

Another study involved 17 people at risk for heart disease and diabetes. They were put on a low-carb, high-fat diet for three weeks. Then, they turned the table and increased carb intake while reducing total fat and saturated fat intake every three weeks for 18 weeks, keeping total caloric intake the same. The more carbs and less fat in the diet resulted in an increase in markers linked to obesity, type 2 diabetes, and heart disease. I know, a very small group of people, but anyway.

So is the fight over?

No, we are still waiting for the knock-out blow. Life is never that simple.

As for saturated fats, these fats are a diverse class of compounds. Some saturated fats elevate bad cholesterol, others have no effect, and some actually increase good cholesterol. Fats in foods are always a mixture. While some foods high in saturated fats, such as processed meats, might be connected to heart disease, other foods high in saturated fat such as dairy have no such effect. And there is also the supposition that some polyunsaturated fats might induce inflammation that in turn can influence the heart disease rate.

And similarly to fats, not all carbs are equal. The monosaccharide, fructose, and the disaccharide sucrose, common table sugar, with half fructose (together with glucose), produce greater degrees of metabolic abnormalities than does glucose alone found in long chains of starch in certain foods and cellulose in plant walls.

If you need to lose weight science is pretty clear. If you eat too little fat, your metabolism won’t be as efficient and will create some waste because of an excess of carbs and/or protein. A slower metabolism and a higher load of waste will interfere with weight loss. On the other hand, high-fat food dampens appetite and can help you eat less and thus lose weight.

Sugar can be fattening indirectly by causing you to eat more. Eating too much sugar will encourage insulin production. If you produce too much insulin it actually causes blood sugar to dip and you feel tired. As you need an energy boost you eat more, and you tend to give in to cravings for more sugar. Of course, that only makes the whole cycle happen again.

But we don’t eat fat or carbohydrates in isolation, we eat them in the form of complex foods with a lot of other necessary components. If you forget weight loss and just want to maintain a healthy diet there is room for good forms of both fat and carbohydrates. With fat you get important fat-soluble vitamins and essential fatty acids, and with complex carbohydrate foods you get minerals, water-soluble vitamins and antioxidants like flavonoids.

What about everything in moderation?

Find the right balance for healthy eating (Photo: Mauro Cateb).

Find the right balance for healthy eating (Photo: Mauro Cateb).

We have said it before, why not everything in moderation as the saying goes. Or did go!

Even that has now been criticised as being too vague and difficult to measure. ‘There are no good or bad foods,” and “all foods can fit into a healthy diet” are variations on the moderation theme. But what exactly is moderation? A new study found that definitions of moderate consumption were related to personal consumption behaviours. Results suggest that the endorsement of moderation messages allows for a wide range of interpretations of moderate consumption.

Healthy eating is about finding a balance between two extremes – deprivation and overindulgence. It is about adhering to strategies and habits that can be maintained long term as part of a lifestyle to avoid a yoyo effect between these extremes.

Call it what you like as long as you don’t give in to your ghrelin urge too often. An occasional binge can be justified to keep you happy. That’s what life is all about, isn’t it?

The war on sugar

The sweetness of ice cream can be overwhelming.

The sweetness of ice-cream can be overwhelming.

The sweet tooth seems to require a treat now and then. But why are most food manufacturers overdoing the sweetness thingy. You have an ice-cream treat and although it initially tastes nice, after half is consumed you feel the sugar molecules crawling in your mouth with the sugar taste lingering for several hours. The same with a blueberry cheesecake. The sweetness is just overwhelming.

I could go on and on. I am not after sugar replacements, I just want the sweetness to be toned down.

Trend to reduce sugar intake

Actually, reducing sugar intake has become a key concern amongst many consumers. In a recent 2,500-strong European consumer survey, a quarter of those asked preferred low sugar food products, findings that seem to confirm the continuing shift in consumer efforts to reduce sugar intake. They also found that more than 60% of those surveyed actively monitored their dietary sugar intake. This might be influenced by the World Health Organisation recommendation to reduce sugar intake to less than 10% of total energy intake, or the more extreme aim to get down to less than 5% for improved health.

Excessive sugar consumption continues to be criticised by the media and health professionals alike, resulting in today’s sugar backlash. This has led to sugar replacing fat and salt as the new dietary pariah in many countries. There is thus a key opportunity for companies to address consumer preferences and adapt their products to carry a low or reduced sugar level. But food manufacturers aren’t listening. Of course, taste differences that consumers are not used to can make or break a popular product – something manufacturers are hesitant to risk. However, why not give us some alternatives?

But still a persistent problem

In reality we seem to go backwards in many respects and the USA is a horror example not to follow. In the last 40 years, fructose, a simple sugar derived from fruit and vegetables, has been on the increase in American diets. Because of the addition of high-fructose corn syrup to many soft drinks and processed baked goods, fructose alone now accounts for 10% of caloric intake for US citizens. But note that this is the average with peaks much beyond this especially in adolescents.

Fructose in soft drinks a culprit.

Fructose in soft drinks a culprit.

And then you should know that a recent study found that, matched calorie for calorie with the simple sugar glucose, fructose causes significant weight gain, physical inactivity, and body fat deposition. The link between increases in sugar intake, particularly fructose, and the rising obesity epidemic has been debated for many years with no clear conclusions as people are not only consuming more fructose through their diets, but also consuming more calories in general.

Thus researchers studied two groups of mice, one group was fed a diet in which 18% of the calories came from fructose, mimicking the intake of adolescents in the USA, and the other was fed 18% from glucose, while both groups had exactly the same amount of calories derived from sugar. The only difference was the type of sugar, either fructose or glucose. The results showed conclusively that the fructose-fed mice displayed significantly increased body weight, liver mass, and fat mass in comparison to the glucose-fed mice.

Given the dramatic increase in obesity among young people and the severe negative effects that this can have on health throughout life, it is important to consider what foods are providing our calories.

More ill effects from too much sugar

A new study highlights one more reason to avoid sugary beverages, processed foods and other energy-dense carbohydrate-containing foods. Regular consumption of sugary beverages was shown to be associated with a 3 times greater risk of prostate cancer. By contrast, healthy carbohydrate-containing foods like legumes, non-starchy vegetables, fruits and whole grains were collectively associated with a 67% lower risk for breast cancer.

A common warning though for these type of studies, the results point only to associations, not necessarily to cause-and-effect, but at least the findings are in line with previous studies. Malignant cancer cells seem to feed on sugar, and diets high in refined carbohydrates may lead to a range of adverse health effects primarily due to their impacts on body fatness and on the dysregulation of insulin and glucose, both of which are factors that may increase cancer risk.

Better control of your brain

So what to do about the sweet tooth. Well, actually it has nothing to do with our teeth per se but rather brain chemistry. Excess sugar consumption has been shown to repeatedly elevate dopamine levels which control the brain’s reward and pleasure centres in a way that is similar to many drugs of abuse including tobacco, cocaine and morphine.

Go for a pill or healthy food? (Photo: Chris de Rham)

Go for a pill or healthy food, your choice (Photo: Chris de Rham).

An Australian research team even went further in showing that if sugar is consumed at current levels in the modern western diet, it can induce structural changes in the brain that impact behaviour by influencing how neurons communicate.

Now you could try medication as the Australian research team observed that the smoking cessation drug varenicline, which is FDA approved, had a similar effect in reducing sugar consumption. Or you could go the more natural way.

Some hope in the war on sugar

There are some tentative steps in industry product reformulation through the development of new sugar-reduced products that you could go for. Or you could just reduce the portion size.

There are also potential government action that might provide future help. A few governments have taken the bold move to introduce a sugar tax as recent years have brought more attention to the role of carbohydrates in our diets and the differences between healthy and unhealthy carbs.

As usual it is your choice.

The odd danger of barbecuing

barbecue

Wire bristles from barbecue cleaning brushes can cause a health emergency.

And you thought that cleaning the barbecue was a safe exercise, think again. New research has examined the incidence of injuries caused by ingesting wire bristles from grill brushes. Yes I am serious, this can actually be a problem!

We usually highlight chemical risks in this blog and there are a few linked to barbecuing. Polycyclic aromatic hydrocarbons easily come to mind as one of the more problematic process contaminants formed during careless barbecuing. They are suspect carcinogens to be avoided if at all possible. Physical risks are less common. Sure you can burn your hands over the barbecue fire when cooking your food. But wire bristles?

Although the peak season for barbecuing is over in Australia as of the writing of this blog in early April, it is soon approaching in the northern hemisphere. Thus the US researchers prompted physicians and consumers to take notice of their findings before the summer grilling season. The researchers reviewed literature and used the Consumer Product Safety Commission’s National Electronic Injury Surveillance System and the consumer reported injury database SaferProducts.gov to derive a national weighted estimate of emergency department visits for wire bristle injury from 2002 to 2014. They estimated that there were 1698 cases presented to emergency departments in that time. However, they further considered it likely that the issue is under reported. Because of the uncommon nature of wire bristle injuries, people may not be as mindful about the dangers and implications. Awareness among emergency department physicians, radiologists, and otolaryngologists is particularly important so that appropriate tests and examinations can be conducted.

mouth

Be careful with what you put into your mouth.

The most common location of injury was the oral cavity and the oropharynx which includes the throat and tonsils. In all databases, injuries involving the esophagus and head and neck were more frequent than abdominal injuries.

So another reason to exercise caution when cleaning grills with wire-bristle brushes. It might pay off to examine brushes prior to each use and discarding if bristles are loose. And why not inspect cooking grates prior to cooking to be on the safe side even for this odd problem.