Nutritional supplements are used by over 40% of UK adults and the industry is worth over £200 million per year! Where possible, nutritional deficiencies should be resolved by dietary means, but this is not always achievable and those with a severe deficiency or an established illness may require a more rapid resolution than can be obtained by diet alone.

Factors to consider before taking a supplement:

1. Check for certification – certification can come from the National Nutritional foods Association, NSF or the United States Pharmacopeia.

2. Check manufacturing processes – The way certain ingredients are processed effects their quality, cheaper processing extraction methods may reduce the viability of the product and safety.

3. Why are you supplementing in the first place? It’s always good to have a reason as to why you’re taking a supplement.

4. What form is the nutrient in? – Liquid forms are excellent for absorption, as some tablets contain excipients which you do not necessarily want. Food form supplements are thought to be more bio-available, however more research needs to be done.

5. Dosage – It is vital to get the right dosage before taking any supplement, and most supplements do tell you the dosing on the packaging. However be sure to work with a practitioner if you’re wanting to do higher doses to achieve a more therapeutic affect.

6. Are you taking any other medication? Check for interactions before taking any supplements as they could react with any current medication you’re taking, or ask your GP. is a great site to use to check for interactions.

7. Excipients e.g maltodextrin, corn fibre etc – Most supplements contain a lot of excipients and some artificial preservatives, look out for ones with less artificial ingredients!

Are you at risk of deficiency?

Stress and illness
Stress is a reason to take supplements. Illness, especially recovering and rebuilding from illness, is another reason to make sure we are getting our basic nutrient needs. Please remember supplements do not replace A GOOD DIET. Often when we are ill we do not feel like eating, or our digestion functions are not working properly.
When a healthy person is under more stress or during times of change of early illness, or if symptoms and illnesses are coming more frequently, a specific supplement program may be helpful. B complex and Vitamin C and other minerals have generally shown to improve general mental health, and reduce subjective stress.

Those of us who have lead busy, active lives, drive cars in traffic regularly, live in the city, work at stressful jobs, or don’t necessarily eat well, they could benefit from daily basic regimen of nutritional supplements. Taking supplements will ensure we do not become deficient in any nutrient, and will help balance out the effects of a stressful lifestyle so we will not break down and become ill.

After injury or before and after surgery, extra nutritional supplements may be helpful in supporting rapid healing, including vitamin A, Vitamin C and zinc can help aid tissue repair.

People who are dieting or go on special or limited diets because of allergies, would benefit from a basic general supplement program to ensure all essential micronutrient requirements are met.

Vegetarians and Vegans
Consider these certain nutrients that may be lacking in your diet: Omega 3 fatty acids, Vitamin A, Vitamin B12, Iron, Calcium, zinc, selenium, and choline.

I hope now you will think twice before diving in a filling your cupboards with lots of supplements! There is no substitute for a good diet.

Factors that affect absorption of supplements and how they should be taken

Water soluble vitamins – Most B vitamins and Vitamin C should be taken with food. Vitamin C does not stay in the body, it is urinated out quickly! Also most vitamin C supplements contain artificial sweeteners like sucralose, and anything artificial isn’t really beneficial for your gut health.

B vitamins – They are water soluble so your body will not store these vitamins in the body, so it is vital to keep eating a diet high in a variety of B Vitamins for general health. B vitamins are essential for nerve function, liver, skin health, fetal growth during pregnancy, and a healthy brain. I would always choose a methylated formula…

Active forms – Are you taking active forms of the B vitamins? Check the supplement to see if it comes in the active forms for better utilisation within the body, because if you’re poor methylator you will not convert the B Vitamins very efficiently within the body. The active form of B6 is pyridoxal 5′ phosphate. Methylation is a chemical reaction that occurs in every cell and tissue in your body, it’s role is to help the enzymes in our bodies work efficiently. Enzymes are proteins that act like switches for chemical reactions – they initiate very important processes in every cell and tissue. Methylation processes can cause a variety of issues including stroke, depression, migraines, fertility and many more.

Fat soluble Nutrients

Vitamins A,D,E, K and CoQ10 are best taken with food that contains at least 3g of fat.
Essential fatty acids take with food.

Amino acids
Ideally with CHO foods/drinks or on empty stomach.

Best taken with food as they require stomach acid for digestion.

Absorption of nutrients

– Most absorption occurs in the duodenum, and Jejunum and Vitamins A,D,E and K in the lleum.
We must absorb minerals from the digestive tract to make them available for tissues and cells (minerals are stored in your cells), so your digestive system needs to be in good shape!

Absorption can be as little as 1-20%!

Low stomach acid – Can cause absorption issues e.g. if you’re post menopausal, highly stressed and the elderly. Low stomach acid can lead to decreased absorption of ferric iron. Further research is needed to determine the effects of low stomach acid secretion on mineral bio availabilities from high fibre and phytate containing plant foods.

Phytates (compunds found in grains, legimes, nuts and seeds), oxalates, fibre, unabsorbed fatty acids and other divalent minerals will slow down absorption.

In some studies it has been demonstrated that caffeine negatively influences calcium balance by reducing renal reabsorption of calcium, and possibly by reducing intestinal calcium absorption efficiency. High caffeine intake may involve considerable renal and intestinal calcium losses.

Forms of nutrients – e.g. magnesium citrate has excellent absorption and magnesium aspartate which is bound to an amino acids, absorption is considered high.

Magnesium absorption requires selenium, parathyroid hormone, vitamin B6 and Vitamin D! It is inhibited by the presence of phytates, fibre, alcohol and excess saturated fat.

Ferrous iron is more soluble and better absorbed than ferric iron – look for supplements in the ferrous state. Ferrous citrate is also well absorbed and can be tolerate by those with sensitive digestive systems. Ferrous Sulphate can cause constipation in some people and it is also inorganic. Always check your blood levels before supplementing with iron, and see a practitioner for correct dosing.

Factors that slow down absorption or iron – phytic acid, tannins (in tea), oxalic acid, calcium, zinc, rapid transit time, Hy Pylori, PPI’s and antacids.

Beta – Carotene – converted within the body to vitamin A on an “as needed” basis, which prevents vitamin A toxicity. Provitamin A carotenoids are less easily absorbed than preformed vitamin A and must be converted to retinol and other retinoids by the body. The efficiency of this conversion is highly variable and dependant on factors like food matrix, food preperation and one’s digestive and absorption capacities.

Vitamin A is recycled and stored in the liver so toxicity if possible.

Vitamin D – Helps to absorb calcium.

Vitamin D3 – Although always best to get from the sun, if you need a vitamin D supplement, D3 (the active form) is the most beneficial to take. Taking a vitamin D3 supplement with K2 is also beneficial as this is also essential for bone health. Exposure to sunlight or dietary intake of vitamin D increases serum concentrations of 25-hydroxyvitamin D.

CoQ10 – The efficiency of absorption of orally administered CoQ10 is poor because of it’s insolubility in water limited solubility in lipids and a large molecular weight. Absorption can be improved with a fatty meal. Products containing solubilizied formulations of coQ10 show enhanced bioavailability as compared with powder-based capsules and tablets.


Braun & Cohen(2010) Herbs and Natural Supplements: An Evidence Based Guide, 3E. Elsevier: Australia Lonnerdal, B. (2010) Calcium and iron absorption–mechanisms and public health relevance. International Journal of Vitamin and Nutrition Research. (2015),Volume 80, pp. 293-299

Abraham GE, Flechas JD. (1992) Hypothesis: Management of fibromyalgia: rationale for the use of magnesium and malic acid. J Nutr Med 1992;3:49-59 Engen et al (2015) Effects of transdermal magnesium chloride on quality of life for patients with fibromyalgia: a feasibility study. Journal of Integrative Medicine. Volume 13, 2015 Issue 5 [online] Available at:

Braun & Cohen(2010) Herbs and Natural Supplements: An Evidence Based Guide, 3E. Elsevier: Australia