I have a healthy diet: do I really need vitamins? Part. 2

The VITL Nutrition Team / Dec 7, 2016

Often we get asked why it is necessary to take vitamins. Surely a varied and balanced diet provides everything you need, right?


In Part 1 we looked at how farming, soil quality, and certain lifestyle habits contribute to potential vitamin and mineral deficiencies in the body. But what other factors do we need to take into account?

1. Stress

The general understanding of how stress crucially affects our health is gradually increasing. Some levels of stress can be healthy and help push and strengthen the mind and body. However, prolonged or very high levels of stress can have a negative impact both mentally and physically. Stress creates greater physiological demands on the body, increasing its need for energy, oxygen, and circulation. This creates a greater need for vitamins, minerals, and nutritionally dense food. Ironically, people suffering from stress are often drawn towards sugary or fatty foods, which lack the necessary nutrients the body needs during these times, often exacerbating the problem. Stress not only requires higher levels of nutrients but also depletes levels of existing vitamins and minerals in the body, exacerbating deficiencies.  

Which key nutrients are affected?

Omega 3

Omega 3 fatty acids are needed by your brain for the formation of healthy nerve cells, and studies show that omega 3’s have been associated with lower risk of depression1. Alpha-linolenic acid (ALA) is the parent omega 3 and can be metabolized in the liver to the longer chain omega 3 eicosapentaenoic (EPA) and docosahexaenoic acid (DHA). Stress can compromise this conversion. EPA and DHA have an array of health benefits and insufficient levels in the body may affect many aspects of cardiovascular function including inflammation, peripheral artery disease, major coronary events, and anticoagulation. EPA and DHA have been linked to promising results in prevention, weight management, and cognitive function in those with very mild Alzheimer’s disease2.

Vitamin C

Levels of vitamin C can be affected by both emotional and physical stress. Stress can increase a person’s requirement for vitamin C to maintain normal blood glucose levels and resistance to infection and disease. Vitamin C has been shown to support the adrenal glands, helping with regulating cortisol levels and it can help the body recover from emotional and physical stress, which may otherwise weaken adrenal glands and increase fatigue3.


Magnesium and stress are very closely linked. Magnesium is needed for a variety of tasks including muscle relaxation, fatty acid formation, and heartbeat regulation. Stress can increase magnesium loss from cells4.

Vitamin D

Vitamin D is a steroid hormone which once consumed or synthesized, needs a receptor in the body in order to become active. A class of hormones called glucocorticoids is known to decrease expression of vitamin D receptors. Cortisol, which is known as the ‘stress hormone’ is the most well-known glucocorticoid and can inhibit the expression of vitamin D. Cortisol helps the body adapt to stressful situations but when released in high amounts, can affect the vitamin D receptors in your body, meaning the vitamin will remain inactive in the body.


Stress has been shown to reduce your microflora, or ‘good’ bacteria in the gut, and increase the growth of pathogenic or ‘bad’ bacteria. Probiotics increase the growth of good bacteria and prevent the pathogenic bacteria from populating. According to studies, probiotic bacteria have the potential to alter brain neurochemistry and treat anxiety and depression-related disorders5.

2. Pollution

For those of us who live or work in a city, exposure to heavy pollution is unavoidable. Pollution has been recorded as preventing adequate sunlight penetrating the earth’s surface6. Free radicals in the atmosphere, such as nitric oxides, sulfur dioxide, and ozone, are well-known oxidants and have been reported to induce organ and cellular damage via generation of free radical species7.

Which key nutrients are affected?

Vitamin D

Pollution is having a huge impact on our vitamin D levels. The Science Advisory Committee on Nutrition (SANC) have recommended we double our recommended intake of vitamin D from 5 to 10 µg/day8. At present, the national average intake is 2.8 µg/day so upping our intake of vitamin D needs to become a priority for most of us.  

The body can make vitamin D itself, but in order to do so, it requires sunshine. Sun rays on the skin converts cholesterol to an intermediate compound, which then travels to the liver, then to the kidneys, where it is converted to vitamin D. The lack of sunshine in the UK is made worse by a lack of attainable UVB rays that reach the earth’s surface. The level of atmospheric pollution is one of the chief actors in determining the percentage of the ground level of UVB and studies have shown that living in a place with high levels of air pollution, has a significant influence on vitamin D status 8.

Vitamin A

Environmental pollutants can also cause vitamin A deficiency. Pollution can accelerate vitamin A metabolism and the breakdown of the vitamin in the body. The mechanisms responsible for these events most likely include altered activities of enzymes that are involved in critical vitamin A metabolic pathways9.

Vitamin E

Vitamin E is accepted as nature's most effective lipid-soluble antioxidant, protecting against cell damage caused by pollution, which in turn leads to degenerative diseases10.

3. Omega 3:6 ratio

It is suggested that human beings evolved on a diet with far higher levels of omega 3 essential fatty acids (EFA’s) than omega-6 EFA’s11.  Western diets are deficient in omega 3 fatty acids and have excessive amounts of omega 6 fatty acids compared with a diet on which human beings evolved and their genetic patterns were established. Excessive amounts of omega 6 have been linked to cardiovascular disease, cancer and inflammatory and autoimmune disease11, however, a sufficient amount of omega 3 in the diet can have a suppressive effect and could balance out excessive Omega 6 consumption11. Omega 6 fatty acids are classed as polyunsaturated fats and are growing in prevalence in modern diets. Vegetable oil, mayonnaise, fast food, biscuits, cakes and sausages all contain high levels of these fats.

Omega 3 is chiefly obtained from the consumption of fish, or a vegetarian source is algal oil. Oily fish such as mackerel, anchovies, sardines and salmon are excellent sources, however, a recent study has shown levels of beneficial omega 3 oils in farmed salmon have fallen significantly in the past five years. At VITL, we use krill oil in our omega 3 which is absorbed much better by the body than fish oil12, without the fishy aftertaste found in some fish oils.

At VITL, we understand that you are unique. Your lifestyle, diet, and goals are individual to you and so, therefore, are your nutritional needs. With our new app, we are able to assess your health status through our AI-powered nutritionist and formulate a bespoke nutrition pack, tailored to your personal needs...

  1. https://www.ncbi.nlm.nih.gov/pubmed/27766299

  2. http://advances.nutrition.org/content/3/1/1.full

  3. http://www.omicsonline.org/open-access/nutrient-and-stress-management-2155-9600-1000528.php?aid=76425

  4. https://doi.org/10.1080/07315724.1994.10718432

  5. https://www.ncbi.nlm.nih.gov/pubmed/23384445

  6. https://www.ncbi.nlm.nih.gov/pubmed/20799984

  7. https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/537616/SACN_Vitamin_D_and_Health_report.pdf

  8. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2940914/

  9. https://doi.org/10.3181/00379727-201-43494

  10. http://ajcn.nutrition.org/content/53/4/1050S.short

  11. http://www.sciencedirect.com/science/article/pii/S0753332202002536

  12. https://lipidworld.biomedcentral.com/articles/10.1186/1476-511X-10-145