There are some necessary dietary supplements

Don’t believe we are all bad, we have kept faith in a few dietary supplements even if we haven’t said so. But the list is quite short. There are certainly life situations where a supplement can be necessary as long as you can trust that what they say on the label is actually what’s in the product. And no surprises in the bottle. So here we have four supplements worth giving some thought.

Folate inadequacy

Spinach a good food source of folate (Photo: Jason Bachman).

Spinach is a good food source of folate (Photo: Jason Bachman).

For pregnant women extra folate can certainly be needed. Folate is a B-group vitamin. It is known as folate when it is found naturally in food, such as green leafy vegetables, and as folic acid, the more stable form, when it is added to food, such as bread and breakfast cereals, or used in dietary supplements. Folic acid refers to the oxidized synthetic compound, whereas folate refers to the various tetrahydrofolate derivatives naturally found in food. Folate is essential to the healthy development of babies in early pregnancy and deficiency can lead to neural tube defects such as spina bifida.

For women past childbearing age, and for men in general, excessive doses of the synthetic form of this nutrient are not necessary, and may even be harmful as it has, although not conclusively, been linked to cancer. Despite the risks associated with high levels of folic acid intake, it is well established that adequate folate intake from the consumption of folate-rich foods is essential for health.

Folate is an essential micronutrient required for the synthesis of ribo- and deoxyribonucleic acids (RNA and DNA) and thus for cell division and tissue growth, methylation reactions and amino acid metabolism. Folate aids the complete development of red blood cells, reduces levels of homocysteine in the blood, and supports nervous system function.

Excellent sources of dietary folate include vegetables such as romaine lettuce, spinach, asparagus, turnip greens, mustard greens, parsley, collard greens, broccoli, cauliflower, beets, and lentils.

We still give a green light for folate supplementation, but mainly for women of childbearing age. Folic acid supplements should contain 400 µg of folic acid to be useful. More information can be gained from a 2014 European Food Safety Authority opinion. However, there is a caveat. A study published in early 2015 showed that too much of a good thing, even for pregnant females, may predispose their daughters in particular to diabetes and obesity later in life. At least for rats. So stick to the recommended dose.

Iron deficiency

Haeme iron in meta more easily absorbed (Photo: Ryan Kazda).

Haem iron in meat more easily absorbed (Photo: Ryan Kazda).

Iron is a mineral that plays a key role in the making of red blood cells. Too little iron may lead to anaemia, a low level of red blood cells. Anaemia can cause fatigue and other symptoms.

You can certainly get enough iron from food. Iron absorption is best (15-18%) from foods that contain haem iron. Red meat, seafood and poultry are the best sources of haem iron. Iron absorption from foods that contain non-haem iron is much lower (<5%). Non-haem iron is predominantly found in plant foods such as cereals, vegetables, legumes and nuts.

In case of a deficient diet it is also possible to use iron supplements to improve iron status. Iron supplements are often used to treat anaemia caused by pregnancy, heavy menstrual periods, kidney disease and chemotherapy. Iron supplements are commonly recommended for infants and toddlers, teenage girls, and women who are pregnant or of childbearing age to help prevent anaemia.

But too much iron can lead to poisoning and cause many serious problems including stomach and intestinal distress, liver failure, dangerously low blood pressure, and death.

So again a green light for use of iron supplements but only after a diagnosis of anaemia.

Vitamin D supplementation

Vitamin D is important for several bodily functions, particularly for the maintenance of strong bones. It does that by regulating the absorption of calcium and phosphorus. Deficiency can lead to rickets in infants or osteoporotic fractures in the elderly. There are also non-skeletal actions of vitamin D with suggestions that deficiency might result in a higher incidence of cancer, cardiovascular diseases, diabetes, infections, neuropsychiatric disorders, and a higher risk of death in predominantly elderly participants living independently or in institutional care. However, there is a growing body of evidence indicating that vitamin D is unlikely to prevent non-skeletal disorders. Still there is strong support for its use from many prominent members of the research community.

Ten minutes of sunshine a day is sufficient to replenish vitamin D stores (Photo: Björn Burton).

Ten minutes of sunshine a day is sufficient to replenish vitamin D stores (Photo: Björn Burton).

The two most important forms of the vitamin are vitamin D3 (also known as cholecalciferol) and vitamin D2 (ergocalciferol) that are converted in a two-step process in the liver and kidneys to calcitriol, the biologically active form. Calcitriol circulates as a hormone in the blood, regulating the concentration of calcium and phosphate in the bloodstream and promoting the healthy growth and remodeling of bone.

Sun exposure is an easy, reliable way for most people to get vitamin D. In most situations, 30 minutes of skin exposure of the arms and face to sunlight can provide all the daily vitamin D needs of the body.  Just 6 days of casual sunlight exposure without sunscreen can make up for 49 days of no sunlight exposure. Body fat acts like a kind of storage battery for vitamin D. During periods of sunlight, vitamin D is stored in fat and then released when sunlight is gone. Vitamin D can be found in small amounts in a few foods, including fatty fish such as herring, mackerel, sardines and tuna. To make vitamin D more available, it is added to dairy products, juices, and cereals.

Vitamin D deficiency has become a populist issue worldwide with increased testing for vitamin blood levels. A level of 20-50 ng/mL is considered adequate for healthy people.  If the higher level of 50 ng/mL is used as a cut-off point, a large part of the population would be deficient. At levels less than 12 ng/mL everyone agrees that supplementation would be needed.

But with so many other good things, too much can be harmful. The European Food Safety Authority has sett an upper tolerable level of vitamin D intake at 100 µg/day. More than this level could result in hypercalcaemia and lead to abnormal heart rhythms, muscle weakness, depression, abdominal pain, nausea and vomiting.

We also give a green light for vitamin D supplements but only for people with conditions such as osteoporosis or chronic kidney failure that are known to decrease vitamin D, for risk groups such as people with dark skin, and after testing that show too low blood levels of vitamin D.

A caution is in place. Supplement intake levels between 5-20 µg/day is recommended in different countries and dependent on age. Thus a supplement tablet should not contain more than a total of 20 µg. The Norwegian Food Authority (Mattilsynet) has just banned a range of vitamin D supplements on the market containing more than six times the allowable level or 120 µg per tablet so be careful what you buy. And remember that you also get some vitamin D by just stepping outside in the sun.

Omega-3 fatty acids

Omega-3 fatty acids are important for normal metabolism. The three types of omega-3 fatty acids involved in human physiology are α-linolenic acid (ALA) (found in plant oils), eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) (both commonly found in marine oils). Unfortunately, humans have only a limited ability to synthesise the more important long-chain omega-3 fatty acids, EPA and DHA from ALA and this is further deteriorating with age.

Fish is the best food source of omega-3 fatty acids (Photo: Johan Munk Wolfhage).

Fish is the best food source of omega-3 fatty acids (Photo: Johan Munk Wolfhage).

There are many health benefits of omega-3 fatty acids. Research shows strong evidence that EPA and DHA can help lower triglycerides and blood pressure. And there are studies showing that omega-3 fatty acids may help with other conditions, including rheumatoid arthritis, depression, and many more. It is clear that we need omega-3 fatty acids for numerous normal body functions, such as controlling blood clotting and building cell membranes in the brain.  And dieticians say that there’s no question that eating fish provides tremendous value in reducing risk for cardiovascular disease.

There aren’t many side effects reported for omega-3 fatty acids. Some people can experience intestinal problems and gas formation, but not much else. So there should be all go for eating more fatty fish or taking fish oil supplements.

But as usual there is a catch when relying on supplements. A recent study has shown that most fish oil capsules sold in Australia and New Zealand have less omega-3 fatty acids than their labels claim. Only three of the 32 fish oil capsules tested by researchers from Newcastle University and Auckland University contained the same or higher amount of the polyunsaturated fats declared on their labels.  Two products failed to hit even a third of what was claimed. Further, the active ingredients of fish oil are fragile, and if they’re exposed to oxygen, to light, to increasing temperature above freezing, they will degrade. And true enough the researchers discovered worryingly high levels of oxidisation.


What we can learn is that barely a handful of food supplements are worthwhile and mainly if a deficiency has been established. So by all means go ahead. But even if the supplements are recommended you don’t know if you get what you pay for. Unless the controls of the supplements industry are improved it might be better to stay away.

Related articles

Food is in while supplement pills are out

Skewed diet and no pills (Photo: Tony Evans)

Skewed diet and no supplements go together (Photo: Tony Evans)

This blog is not for you if your main meals consist of McDonald’s burgers and KFC chickens, you only drink soft drinks and Red Bull, and you eat doughnuts instead of wholegrain bread, because you would never even contemplate to take vitamin or mineral supplements. You might need it though.

But if you eat a varied diet and worry about your nutrition, it is very likely that you would also supplement your diet with multivitamins and minerals. This is a real conundrum because if you are in the latter group you actually satisfy your vitamin and mineral needs through your diet and don’t need the supplements.

And did you know that the supplements can actually do more harm than good? I guess you didn’t. It is all about p53, but more about that later.

Too much of a good thing

Don’t get me wrong, vitamins and minerals are absolutely necessary for the body to maintain good health. This has been known for a reasonably long time, with possibly the best example being the complete cure of scurvy with vitamin C. Scurvy was a terrible disease that plagued humans long back through recorded history, but now a rarely seen condition. Many other vitamins and micronutrients are required for good health.

Antioxidants, like selenium, and the vitamins A, C and E, fight free radicals that can damage DNA, cell membranes, and the lining of arteries. Deficiencies can cause all sorts of diseases, some of them very serious. Several studies have shown that people who eat more fruits and vegetables that contain plenty of antioxidants have a lower incidence of cancer and heart disease and live longer. The logic is obvious that if people who eat lots of fruits and vegetables are healthier, then people who take supplemental antioxidants should also be healthier.

But not so. Remarkably, studies involving tens of thousands of subjects have shown that high doses of vitamins and supplements, rather than being helpful, lack beneficial effects or can sometimes even be harmful to health. It seem that humans are adapted to getting nutrients from whole foods and not through pills. Most nutrients require enzymes, synergistic co-factors and organic mineral-activators to be properly absorbed. While these are naturally present in foods, they are often not included in synthetic vitamins with isolated nutrients.

And I have the science to prove it.


Vitamin and mineral supplements can even be harmful (Photo: Steven Depolo)

An evaluation of 38,772 older women found that several commonly used dietary vitamin and mineral supplements, including multivitamins, vitamins B6, and folic acid, as well as minerals like iron, magnesium, zinc, and copper, were associated with a higher risk of total mortality. Iron was of particular concern since it was strongly and dose dependently associated with increased total mortality risk.

A study of 35,533 men found that the risk of prostate cancer increased for the men taking vitamin E, selenium, or both. Although the increased risk was small, it was clear that neither of these supplements was helpful against prostate cancer.

In reviewing 27 trials looking at the efficacy of vitamin supplements in 400,000 adults with no nutritional deficiencies, the typical supplement customers, no clear evidence of a beneficial effect of supplements on all-cause mortality, cardiovascular disease, or cancer could be found.

Daily multivitamins to prevent cognitive decline among 5,947 elderly men didn’t improve overall cognitive performance or verbal memory. After 12 years of follow-up, there were no differences between the multivitamin and placebo groups.

Many more trials have assessed the role of vitamin and mineral supplements in primary or secondary prevention of chronic disease and have consistently found no beneficial effects or even possible harm. Beta-carotene, vitamin E, and possibly high doses of vitamin A supplements have been seen to increase mortality. How is that?

It might be the p53

The p53 is a gene that has been dubbed the guardian of the genome, your DNA. Its job is to detect and destroy cells with defective DNA, including early cancer cells. Of course you don’t want to interfere in that process, but you might inadvertently do just that by taking extra antioxidants. A team of Swedish scientists has now proved that antioxidants can fuel growth of lung cancers. Antioxidants are supposed to protect healthy cells from chemically unstable oxygen molecules that can damage DNA and cause cancer. But they also shut off the p53 gene, thus allowing cancer cells to grow and divide faster than usual.

So the research results presented above that seemed a bit suspicious at first now has a plausible explanation. Basically, antioxidants help early tumours to survive and grow and can thus increase mortality. The opposite to what you want.

Stop the pill popping

Fruit (Photo: Mariia Kravtsova)

A balanced diet with plenty of fruit and vegetables is sufficient for most people (Photo: Mariia Kravtsova)

The simple truth for the general population with no clear evidence of micronutrient deficiencies is that most supplements do not prevent chronic disease or death. Their use is not justified, and they should be avoided since some might even be harmful. Supplements are only needed where there is a demonstrable micronutrient deficiency. The most promising data in the area of nutrition and positive health outcomes relate to dietary patterns, not nutrient supplements. In most cases, eating lots of fruit and vegetables, and a balanced diet, will provide all micronutrients and vitamins needed. So maybe you should skip that burger tomorrow and go for an apple.