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Making sense of supplements


Making sense of supplements

With such a vast range of supplements and an abundance of information about them available to customers, it can be confusing to know which ones are suitable, but pharmacy teams can help

A balanced and healthy diet is likely to provide all the nutrients most people need to help maintain good health and wellbeing. However, in reality, individuals’ diets are not always made up of a variety of food groups in the right proportions. For this reason, a dietary supplement may help to optimise vitamin and mineral levels – but where to start?

Pharmacies are often the first port of call for customers wanting advice on selecting suitable supplements and how much they should take, as well as answers to countless other questions. It’s therefore important for pharmacy staff to be up to date on the latest guidance and to have a good foundation of knowledge about different types of supplements so they can help customers optimise their health.

Vitamin and mineral supplements are classified as food supplements in the UK and are regulated under the Food Safety Act 1990. Emma Derbyshire, nutritionist and spokesperson for the Health and Food Supplements Information Service (HSIS), says that “the food law does not permit any food to make any claim, or imply that it can treat, prevent or cure any disease or adverse medical condition”. She recommends that customers are advised to choose a quality brand with clear labelling that states the quantity of the nutrients in the product.

A numbers minefield

The labelling on dietary supplements gives a nutrient reference value (NRV), which is the amount of vitamin or mineral that is needed by an average person daily to prevent deficiency, based on guidance set by the European Union. 

The labelling should include the amount of nutrient in the product – quoted in either micrograms (mcg/µg) or milligrams (mg) – as well as the proportion of the NRV value, stated as a percentage. For example, a product containing 80mg of vitamin C will have a NRV of 100%, as the recommended intake of vitamin C is 80mg daily. In addition, a product containing 160mg of vitamin C will have a NRV of 200% as this is twice the recommended daily intake of vitamin C. 

It is safe to exceed the NRV of most vitamins and minerals, as long as the safe upper level (SUL) or the guidance level (GL) is not exceeded. It is important to note that the safe upper level refers to the amount of nutrient intake from a supplement or food fortification, not through normal dietary intake. Checking the safe upper level of a nutrient, especially fat-soluble vitamins such as vitamin A, D, E and K, is also necessary, as these can build up in the body to harmful levels. Particular care should also be taken if more than one product containing the same ingredient is recommended. 

Up-to-date NRVs and SULs for vitamins and minerals can be found on the HSIS website, at:

Helpful or hype?

People have wide-ranging opinions about supplements and the reasons why they might want to start taking them vary. It could be that someone is worried about hair loss. Someone else may be concerned about getting ill and want to try to boost their immunity. Or it could even be that someone’s friend has recommended a “wonder” supplement for joint pain and they want to try it out. Whatever their reason, it is important to ask questions to understand why they want to take supplements and then work together to select the ones that will be the most suitable. 

Emma says that there is research to show that UK diets are not generally healthy, with below recommended intakes of fruit and vegetables, fibre and omega-3 fatty acids across the population, which could lead to deficiency for some people in the short- as well as longer-term. However, it is difficult to know if a customer is deficient in certain vitamins or minerals. Emma says customers may have non-specific symptoms that arise from a low nutrient intake from a poor diet. These symptoms may include tiredness, lack of energy, poor immune function and brittle nails and hair. Emma explains that for some vitamins, a specific deficiency disorder will occur. For example, vitamin C deficiency will cause scurvy and deficiency of vitamin D can cause bone disease such as rickets in children and osteomalacia (soft bones) in adults. While these are difficult to diagnose in the pharmacy, if customers are worried, they can be referred to their GP for further investigation. 

Clinical nutritionist Suzie Sawyer comments that the general lack of variety of nutrients in the UK diet means that it is wise to take a daily multivitamin and mineral supplement. These contain a wide variety of nutrients and, if they are included in the recommended amounts, can act as a kind of nutritional safety net. Suzie also advises that all children aged six months to five years, should be given a vitamin A, C and D supplement, while adults and children should take a daily vitamin D supplement of 10mcg in line with Government recommendations. If an infant is drinking follow-on or growing up milk, these are fortified with some nutrients and therefore the labels should be checked to see if any topping up is required.

Particular care should also be taken if more than one product containing the same ingredient is recommended

Diet distress

There is concern about an enhanced risk of nutritional deficiencies for customers who move to following a vegetarian or vegan diet. The key nutrients that could be an issue for these people are iron, vitamin D, vitamin B12, calcium and zinc. All of these are found in animal-sourced foods, but tend to be less bioavailable or present in smaller amounts in plant foods.

A new survey commissioned by the HSIS of 1,000 vegetarian and vegan adults in the UK highlights worrying gaps in the knowledge about nutrients in people following these diets. It found that 28 per cent of vegans and 13 per cent of vegetarians were diagnosed with a nutrient deficiency following a blood test.

“Many people start a vegetarian or vegan diet without doing any research at all. Simply cutting out whole food groups without prior planning isn’t ideal as most animal and marine foods are a good source of essential nutrients. For example, oily fish provides omega-3 fatty acids and vitamin D, meat contains iron and zinc, and dairy is a source of vitamin B12, iodine and calcium,” explains Carrie Ruxton, dietitian and HSIS adviser. “These nutrients are needed to support health, but often people following vegetarian or vegan diets aren’t aware that some of these nutrients can be tough to get from plant sources.”

A customer who is following a vegetarian or vegan diet may benefit from a multivitamin supplement, together with a vegan omega-3 supplement. 

But it’s not just vegetarians and vegans who might be limited in their iron intake. Emma says young women often have diets lacking in minerals such as magnesium, calcium, zinc, selenium, iodine, copper and, in particular, iron. She states that women aged 19-50 years old have a higher iron requirement than men. However one in 10 women have iron deficiency that is a cause of fatigue. Recommending a suitable multivitamin and mineral supplement together with an iron supplement for young women is therefore a good option. An iron supplement may also be suitable for women who have heavy periods or during pregnancy and these customers should be referred to the pharmacist for further advice.

Sunshine supplement

Vitamin D helps regulate the amount of calcium and phosphate in the body, both of which are needed to keep bones, teeth and muscles healthy.

According to the NHS, from late March/early April to the end of September, most people should be able to get all the vitamin D they need from sunlight. However, during the autumn and winter months, there is not sufficient sunlight for the body to make its own vitamin D. The vitamin is found in a few food sources. However, the levels in these are rarely sufficient. 

How much?

The Department of Health and Social Care recommends:

Breastfed babies from birth to one year of age should be given a daily supplement containing 8.5 to 10 micrograms of vitamin D

Formula-fed babies only need a vitamin D supplement when they’re having less than 500ml (about a pint) of infant formula a day, as infant formula is fortified with the vitamin

Children from the age of one year and adults need 10 micrograms of vitamin D a day during the autumn and winter. This includes pregnant and breastfeeding women 

For people at risk of vitamin D deficiency, such as those with dark skin and those who do not spend a lot of time outdoors – whether that’s because they work indoors or are frail and/or housebound – a daily supplement containing 10 micrograms of vitamin D is recommended year-round.

Baby on board

Women who are trying to conceive or are pregnant should be advised to take 400mcg folic acid daily as it can significantly reduce the risk of neural tube defects such as spina bifida in their baby.

Some multivitamins for pregnant women and children also contain omega-3, as research shows that the DHA fatty acid component is important in infant development, particularly for early eye and brain development. 

It is important to check the vitamin A content in supplements for pregnant women, as vitamin A is fat soluble and can easily build up in the body to harmful levels if too much is taken. The Department of Health and Social Care advises that just before, and during the first three months of pregnancy, women should not eat liver, or take vitamin A supplements which contain more that the 800mcg NRV, unless it is under medical supervision. Vitamin A – also known as retinol – is teratogenic, meaning it may induce developmental abnormalities in a foetus if taken at high levels during this period.

Cod liver oil and other fish oil supplements should be recommended with caution for pregnant women due to their high vitamin A content.

It is wise to take a daily multivitamin and mineral supplement

Don’t forget the omega-3s

The omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) are naturally found in oily fish such as sardines, salmon, mackerel, and also in flaxseeds (often known as linseeds). 

Research shows that 62 per cent of the UK population do not eat the recommended two portions a week of fish (of which one should be oily), which provides sufficient amounts of these fatty acids. For this reason, recommending an omega-3 supplement to customers may be useful. Increasing omega-3 fatty acids in the body is thought to help produce more anti-inflammatory prostaglandins, which can help to manage and improve the symptoms of joint pain and dry skin. In addition, DHA is a major building block in the cerebral cortex – the part of the brain responsible for memory, language, creativity, emotion and attention. 

For this reason, supplements containing fish oils, krill or flaxseed oil (for vegetarians) can be recommended to customers going through menopause as problems with joint pain, dry skin, cognitive skills or memory are common symptoms.

These supplements can also be recommended for customers wishing to take something to help support heart health, as the EPA found in omega-3 supplements is thought to help discourage the formation of blood clots, assisting the flow of blood freely through the arteries and maintaining good circulation, keeping the heart healthy.

Focusing on the brain

Although it is not a medical diagnosis, brain fog is a general term that is used to describe a series of symptoms, such as memory problems, lack of concentration, inability to make a decision, irritability and poor motivation. Dr Gill Jenkins, GP, comments that there are many different reasons that have been linked to these symptoms such as stress, lack of sleep, pollution and medications, as well as poor diets including processed foods.

Research shows that 65 per cent of the population do not consider the impact of diet on brain health. Dr Jenkins explains that virtually all vitamins are needed in adequate amounts for optimally functioning of the brain and good memory. The same goes for minerals such as magnesium, selenium iodine, zinc and iron, as well as omega-3 fatty acids and polyphenols, which are all vital for brain health. But what are all these?
Polyphenols are micronutrients found naturally in plants and colourful fruits such as grapes, apples, pears, cherries and berries. Diets enriched with polyphenols have shown to induce neurogenesis – a process by which new nerve cells are formed in the brain. This is vital for preserving cognitive function and repairing damaged brain cells affected by ageing and brain disorders. Some supplements specifically formulated to help with brain function may contain polyphenols. 
Omega-3 fatty acids (EPA and DHA) are long chain fatty acids that regulate and improve neuronal transmission , helping to enhance learning and memory. High levels of DHA are found in the brain and are known to play a part in mood, emotional state and cognitive function. However, research shows that average intakes of omega-3s are well below the recommended amount of 250mg of EPA/DHA per day for adults and children over the age of two. See above for more.
Vitamins B3, B5, B6, B12 and folate are potent antioxidants that support against free radicals – which have been implicated in diseases such as cancer, heart disease and Parkinson’s and Alzheimer’s diseases. These antioxidants help to enhance alertness and improve energy levels.
Vitamin D has been shown to reduce sleep disturbances and improve sleep duration and sleep quality in several studies.
Magnesium is thought to help decrease the stress hormone cortisol, as well as promoting relaxation and sleep. 
Tryptophan is an amino acid and a precursor to serotonin, which supports the mood-balancing hormone melatonin, which controls the biological clock’s sleep-wake cycle. 
Co-enzyme Q10 is a naturally occurring nutrient in the body and is also found in many foods. It acts as an antioxidant, which protects cells from damage and supports metabolism and nerve function. 
Korean ginseng is a root often used to support cognitive performance and memory. It may help to maintain mental capacities when tired. 
Rhodiola is a herb thought to help balance emotional and physical stress and may help with improving day-to-day state of mind. 
Ginkgo biloba is an antioxidant-rich herb that has traditionally been used to help maintain healthy cognitive function with increase in age. 

Ashwagandha is referred to as an adaptogen which helps the body cope with daily stress and acts as a general tonic. The roots and berries of the Ashwagandha plant are commonly used in ayurvedic (holistic) Indian medicine and are described as Indian ginseng.


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