Everyone needs small amounts of essential vitamins and minerals to stay healthy and keep their body working properly. Most of these micronutrients can’t be made in the body so they need to come from the daily diet. Although eating a varied, balanced diet should provide sufficient quantities of vitamin and minerals, not everyone can achieve this all of the time, which may lead to nutritional deficiencies and the need for dietary supplements.
According to the UK National Diet and Nutrition Survey, many people are lacking in some key micronutrients, with potentially negative effects on their health. These micronutrients include vitamin D, iron, calcium, folic acid, magnesium, riboflavin and iodine.
“These nutrient shortfalls across all decades of life happen because people skip meals, eat too many nutrient-poor snacks and meals, and don’t eat their five-a-day fruit and vegetables,” says Dr Pamela Mason from the Health and Food Supplements Information Service (HSIS). “The good news is that all of these dietary gaps can be made good by taking a daily multivitamin and multimineral supplement. Bridging the dietary gap across all population groups can futureproof health across the board.”
A balanced diet
Most vitamins and minerals are needed in only small quantities by the body for different processes and functions – such as calcium for the maintenance of bones and teeth, muscle contractions and blood clotting, vitamin E for a healthy immune system, and iron for the production of red blood cells. Individual nutritional needs are based on various factors, including age, gender, diet, lifestyle, stage of life and overall health. A ‘balanced diet’ can therefore mean something different to everyone.
The Department of Health has set Dietary Reference Values for vitamins and minerals for different groups of healthy people, with an estimate of how much everyone needs for good health. According to the department, to provide sufficient amounts of essential vitamins and minerals, a balanced diet should contain:
- At least five-a-day of a variety of fruits and vegetables
- Some high-fibre (preferably wholegrain) starchy foods, such as bread, potatoes, rice or pasta
- Two to three servings per day of milk or dairy foods – or suitable dairy-free alternatives that are fortified with calcium
- Two portions per day of beans, pulses, eggs, fish, meat or other protein-rich foods
- Limited amounts of foods that are high in salt, sugar and fat.
Vitamins and minerals come from various food sources. Vitamin A, for example, is found predominantly in cheese, eggs, oily fish, fortified low fat spread, milk and dairy products, liver and liver products. This vitamin can also be made in the body from beta-carotene, which is found mainly in yellow, red and green vegetables and yellow fruits. Good sources of calcium include milk, cheese and other dairy foods, green leafy vegetables, soya drinks with added calcium, and fish eaten with the bones (such as sardines). Good sources of iron include liver, red meat, beans, nuts, dried fruit and fortified breakfast cereals.
Some vitamins and minerals, such as vitamins A and E, can be stored by the body so they’re not needed every day. However, others, such as vitamins B and C, can’t be stored by the body so need to be replenished daily.
Since not everyone can get enough essential vitamins and minerals for good health from their diet, certain groups of people are recommended to take specific dietary supplements. Vitamin D, for example, can be made in the body, but most people living in Britain don’t get enough sunlight to produce sufficient amounts. Many people also don’t get enough vitamin D from their diet, so the Government recommends supplementation.
The Government’s official recommendations for supplementation are:
- All children aged between six months and five years should be given a daily supplement containing vitamins A, C and D
- Adults and children aged five years and over should take (or should be given) a daily 10mcg vitamin D supplement during the autumn and winter months
- Babies from birth to one year should be given a daily supplement with 8.5-10mcg of vitamin D throughout the year (unless they are consuming more than 500ml of infant formula per day), and children aged one to four years should be given a daily 10mcg vitamin D supplement all year round
- Women who are pregnant, trying to conceive or could become pregnant should take a 400mcg folic acid supplement (or a higher dose if recommended by their doctor) daily from before they conceive until 12 weeks of pregnancy.
Doctors and other healthcare professionals may also recommend, or even prescribe, other vitamin and mineral supplements to certain people. Most women are able to get enough iron from their diet but if they have heavy periods they may be advised by their GP to take a daily iron supplement to prevent or treat iron-deficiency anaemia.
The Royal Osteoporosis Society says that most adults need 700mg of calcium a day to keep their bones healthy, but they may need higher levels if they are taking an osteoporosis medicine or are breastfeeding – this extra calcium should come from their daily diet, but a supplement may be necessary.
Some people take dietary supplements to ease certain symptoms, such as magnesium to ease menopausal symptoms, or vitamin B6, calcium, vitamin D and magnesium for premenstrual syndrome (PMS). According to The Migraine Trust, vitamin B2 (riboflavin) and magnesium may help to reduce migraine frequency and severity.
Some people take a general multivitamin/mineral supplement as health insurance against a less-than-balanced diet – these supplements contain low levels of various vitamins and minerals and act as a top-up. Dietary supplements are available in a variety of forms, including tablets, capsules, gummies, sprays and powders. Some products are aimed at specific age groups, life stages or lifestyle choices (e.g. vegetarians or vegans).
“Supplements can bridge these all-too-common dietary gaps,” says Dr Mason. “An all-round multivitamin and mineral supplement containing 100 per cent of the Nutrient Reference Value (NRV) of a wide variety of vitamins and minerals is a good way to bridge the dietary gap as people tend to be short of several nutrients, not just one. Such supplements tend to be well balanced and provide the amounts of nutrients required to prevent deficiencies.”
Dr Mason says that information and education are key to taking the right supplements, and the pharmacy team is well placed to provide this. “Nutrients (vitamins A, B6, B12, C and D as well as copper, folate, iron, selenium and zinc) are essential for immune function, especially important as winter gets under way,” she says.
“A new report commissioned by the HSIS highlights the importance of nutrition at the menopause and in healthy ageing, although more than a quarter (27 per cent) of people surveyed for this report did not realise nutrient gaps were
“Most adults need 700mg of calcium a day to keep their bones healthy”
Vegetarian and vegan diets
A vegetarian diet doesn’t contain any meat, poultry, fish and shellfish (or by-products from any of these protein sources). A vegan diet cuts out all products of animal origin as well, including dairy foods and eggs. Vegetarian and vegan diets can be highly nutritious, and research shows that these may be healthier than a traditional meat-including diet. Vegetarian and vegan diets tend to be higher in fruit and vegetables, wholegrains and dietary fibre, while being lower in saturated fat. However, they often need planning to make sure they contain all of the essential nutrients, especially in the case of vegan diets.
According to the British National Formulary (BNF), vegetarians and vegans may need to take certain daily supplements, such as vitamin B12, calcium, iron and iodine. This is particularly important for pregnant women and babies. Iron tends to be less well-absorbed from plant sources than from animal sources, although absorption can be increased by including vitamin C-rich foods (such as berries or orange juice). It’s important to have calcium-rich foods daily, as these traditionally come from dairy foods; calcium can be found in some breads or leafy green vegetables, as well as fortified breakfast cereals and dairy alternatives. Vitamin D is important for calcium absorption. Vegans should also make sure they have enough vitamin B12, as vegan sources are limited – these include fortified yeast extract, fortified unsweetened soya drinks and fortified breakfast cereals. Vitamin B12 is essential for healthy blood, the nervous system and the immune system.
Deficiency signs and symptoms
If someone isn’t getting all of the essential micronutrients their body needs, they may become clinically deficient – this means they develop certain symptoms associated with reduced levels of that vitamin or mineral. Usually, these symptoms are mild but they can still be troublesome and may become severe if the deficiency remains untreated.
Severe vitamin C deficiency over three months or more may lead to scurvy, with swollen and bleeding gums, joint or leg pain, or skin that bruises easily. Calcium deficiency can affect bone growth and development, leading to rickets in children or osteomalacia in adults. Iodine deficiency may cause a goitre (swelling of the thyroid gland), while being deficient in iron, folate and other B vitamins can lead to anaemia.
Having low levels of certain vitamins and minerals can cause non-specific signs and symptoms. Early signs of iron-deficiency anaemia, for example, include feeling very tired or short of breath, getting palpitations and having pale skin. Vitamin D deficiency may cause a feeling of being run down and general aches and pains. These symptoms can often be mistaken for stress or getting older, leaving the underlying nutritional deficiency undiagnosed.
Taking too many high-dose supplements can be harmful. Some supplements may contain more than one vitamin and mineral, so people need to check labels carefully to make sure they aren’t doubling up. For example, fish liver oils (e.g. cod liver oil) are high in vitamin A and shouldn’t be taken with additional vitamin A (or some multivitamin and mineral) supplements. Some research shows that taking high doses of vitamin A over time may make bones more likely to break, especially in people at risk of osteoporosis. Pregnant women shouldn’t take any vitamin A supplements (or eat liver or liver products) as having large amounts of vitamin A during pregnancy can harm an unborn baby.
Taking high doses of calcium (more than 1500 mg per day) may cause stomach pain and diarrhoea. Taking very high doses of vitamin D supplements over a long period of time may cause a build-up of calcium in the body, weakening the bones and damaging the kidneys and heart.
Some dietary supplements may interact with medicines or aren’t suitable in people with certain medical conditions. Beta-carotene supplements, for example, aren’t recommended for smokers as they may increase the risk of lung cancer. People with heart disease may be advised not to take vitamin E supplements. Effervescent food supplements can be high in salt.
New CBD safety advice
In October 2023, the Food Standards Agency (FSA) issued new advice on CBD (cannabidiol oil) consumption. CBD has become a popular remedy for various ailments, especially chronic pain, and is available to buy legally, both in food and in food supplements in the form of drops, sprays, oils and tinctures. However, its health benefits are still being researched, and the quality of the products varies. All CBD food products must apply for authorisation before they can be sold legally in Britain.
The FSA now recommends that healthy adults should limit their consumption of CBD from food (and food supplements) to 10mg per day, which is about four to five drops of five per cent CBD oil. CBD shouldn’t be taken by people in vulnerable groups, including children, people taking prescribed medicines (unless they speak to their doctor first) and those who are pregnant, breastfeeding or trying to conceive.
The original advice issued in February 2020 recommended that healthy adults shouldn’t have more than 70mg of CBD per day. The updated advice has been based on the average lifetime exposure to food products containing CBD, such as drinks, oils, sweets, bakery items or drops. Some products will have a higher dose of CBD per serving than 10mg a day, so pharmacy customers should check labels carefully.
“The more CBD you consume over your lifetime, the more likely you are to develop long-term adverse effects, like liver damage or thyroid issues,” says Professor Robin May, chief scientific advisor at the FSA.
“The level of risk is related to how much you take, in the same way it is with some other potentially harmful products such as alcoholic drinks. We encourage consumers to check the CBD content on the product label to monitor their overall daily consumption of CBD and consider if they wish to make changes to how much they take based on this updated advice.”