Millions Of People Heading Into Winter With A Lack Of Immunity Nutrients

New study shows sizeable gap for vitamin D, iron and selenium – all essential for normal immunity

That’s the key finding of a new scientific review entitled: British Dietary Habits and Declining Nutrient Intakes^[1] – from the Health and Food Supplements Information Service – www.hsis.org – which also found that most women lacked folate (also called folic acid) which protects developing infants against spina bifida, a neural tube defect.

Nutritionist and co-author of the new research review, Dr Pamela Mason, comments: “Our in-depth analysis revealed sizeable shortfalls in intakes of essential micronutrients across the UK. Besides the worrying findings on folic acid, a range of other nutrients were affected, many of which are key in helping to protect us from common illnesses, especially winter bugs. Notable examples are vitamin D, iron, zinc and selenium. As it takes time and effort to get our diets back on track, we suggest that people top up with a daily multivitamin and mulitimineral supplement.”

In producing their findings, the study authors evaluated data from the UK National Diet and Nutrition Survey.^[2] Additionally, they incorporated insights from a 2024 real-world survey of 1000 participants reviewing people’s vitamin and mineral knowledge, habits and opinions on diet, nutrient intakes and supplementation.

DIET CONFUSION

“The respondents polled in the new real-world research commissioned by HSIS knew the importance of a healthy diet, but the majority (80%) were really confused about what healthy eating means for them,” says GP and study co-author of the new research review – British Dietary Habits and Declining Nutrient Intakes^[3] – Dr Gill Jenkins. Indeed, nearly half (48%) had no idea about the recommended daily intake levels of nutrients.

D FOR DEFICIENCY

“Overall, one in five people in the UK are clinically deficient in vitamin D,” says Dr Pamela Mason, adding: “And yet vitamin D is essential for optimal immunity, healthy bones and teeth and muscle function.”

Dr Gill Jenkins adds: “Sunshine, rather than food, is the main source of vitamin D during the summer. However, over the winter, it’s hard to get enough vitamin D from the diet. Government experts^[4] recommend that everyone over the age of 1 year should take a daily 10 microgram supplement of vitamin D.”

The immune credentials of vitamin D are highlighted in a 2024 meta-analysis (super-study) from a team of Italian clinicians.[5] They reported that vitamin D supplementation reduced the risk of Covid infections by 60%, concluding there was a “definitive and significant association between the protective role of vitamin D and COVID-19 incidence and [intensive care unit] admission.”

MINERALS IN SHORT SUPPLY

Iron is particularly important for making haemoglobin, a protein contained in red blood cells that transports oxygen around the body. Mild iron deficiency causes tiredness, lack of energy, brain fog and shortness of breath. The NHS[6] says: “If iron deficiency anaemia is left untreated, it can make you more susceptible to illness and infection”.

With more severe iron deficiency, symptoms may include heart palpitations, thinning hair, brittle nails, itchy skin and mouth sores or ulcers. Dr Gill Jenkins comments: “It’s a real concern that half (49%) of girls aged 11–18 years and a quarter of women don’t get enough iron in the diet which increases their risk of iron deficiency anaemia.”

Zinc, too, has a wide range of roles in the body. During pregnancy, infancy, and childhood, the body needs zinc for optimal growth and development. Across all age groups, zinc is vital for normal immunity and has been used at higher doses to help target cold symptoms.

“Zinc deficiency can lead to a range of health problems, including slowed growth, reduction in the secretion of sex hormones in males, alopecia (hair loss), and psychiatric disorders. That’s why it’s worrying that children and young people, in particular, are showing signs of low intakes,” says Dr Pamela Mason. Indeed, 18% of 11–18-year-olds, and 11% of 4–10-year-olds have zinc intakes below the minimum needed for health.

Iodine plays a key role in making thyroid hormone, which is needed for infant growth and brain development. During the early stages of pregnancy, iodine deficiency in mums-to-be can lead to delayed brain development in babies.

“The proportion of teen girls who don’t even get the minimum amount of iodine from the diet has risen from a fifth (19%) to a third (28%)”, says Dr Mason, adding: “These are the next generation of mums-to-be so we need to ensure they’re getting the correct nutrition. Adult women also have low iodine intakes. The issue is probably linked to low consumption of dairy foods and fish due to the plant-based diet trend.”

Selenium, too, plays a critical role in reproduction, thyroid hormone metabolism, DNA synthesis, and protection from oxidative damage and infection. However, in the latest UK diet survey, four in 10 (41%) teen girls and two thirds (66%) of women are at greater risk of selenium deficiency. Selenium is a known immunity-support mineral, adding another reason why we should aim to get enough in the diet.

PREGNANCY RISKS

Folic acid (called folate in food sources) was found to be a key nutrient of concern by the study’s authors. Folate is a water-soluble B vitamin, which is essential for normal cell division, formation of red blood cells and brain function. Deficiency can result in tiredness, weakness, diarrhoea and appetite loss.^[7]

Dr Gill Jenkins warns: “Women throughout their reproductive lives, particularly when planning a pregnancy and for the first three months of pregnancy, are recommended to take a daily 400 microgram folic acid supplement to reduce the risk of neural tube defects^[8]. It’s worrying, then, that two thirds of women in the UK are not taking a folic acid supplement before pregnancy.^[9] Additionally, repeated surveys have found that, in women of childbearing age, blood levels of folate fell by a fifth.”

Dr Pamela Mason adds: “We analysed the proportion of women aged 16 to 49 years with red blood cell folate levels below the threshold for increased risk of neural tube defects in pregnancy, which is 748 nmol/L. Our analysis revealed that the proportion of women with dangerously low folate levels rose from two thirds to almost 90% over a period of 15 years.”

LAST WORD

Dr Pamela Mason in summary notes: “In theory, most of the vitamins and minerals we need can be obtained from a healthy diet. But our findings reveal that this is not happening in real life. With winter approaching – a time of increased transmission of colds, flu and gastrointestinal viruses – it’s crucial for people to supercharge their diets with immune-supporting nutrients as well as making sure their daily dietary habits are in good shape for all seasons. A simple way to bridge the gap is for everyone to take a multivitamin and multimineral supplement all year round to ensure their health and wellness is not short of vital nutrients like vitamin D, Zinc, Iron, Selenium, Iodine, B vitamins, Vitamin C and more.”

https://www.hsis.org/wp-content/uploads/2024/10/British-Dietary-Habits-and-Declining-Nutrient-Intakes.pdf

ABOUT HSIS: HSIS (the Health and Food Supplements Information Service) is a communication service providing accurate and balanced information on vitamins, minerals and other food supplements to the media and to health professionals working in the field of diet and nutrition. Find out more at www.hsis.org.

^[1] Mason P et al. (2024). British Dietary Habits and Declining Nutrient Intakes. In press. Nutrition and Food Technology Journal.

^[2] National Diet and Nutrition Survey: Years 9 to 11 (combined) of the Rolling Programme (2016/2017 – 2018/2019). https://www.gov.uk/government/statistics/ndns-results-from-years-9-to-11-2016-to-2017-and-2018-to-2019.

^[3] Mason P et al. (2024). British Dietary Habits and Declining Nutrient Intakes. In press.

^[4] SACN (2016). SACN Vitamin D and health report. Available at: https://http://www.gov.uk/government/publications/sacn-vitamin-d-and-health-report. (accessed 12 January 2021).

[5] Sartini et al. (2024) https://pubmed.ncbi.nlm.nih.gov/38474807/

[6] https://www.nhsinform.scot/illnesses-and-conditions/nutritional/iron-deficiency-anaemia/#about-iron-deficiency-anaemia

^[7] Mason P (ed) (2024). Dietary Supplements. London: Pharmaceutical Press. Available at: http://www.medicinescomplete.com/

^[8] NICE (2014). Public health guideline: Maternal and child nutrition (PH11). https://www.nice.org.uk/guidance/ph11/chapter/4-recommendations.

^[9] McDougall B et al. (2021). Health behaviours in 131,182 UK women planning pregnancy. BMC pregnancy and childbirth, 21: 530. https://doi.org/10.1186/s12884-021-04007-w

µg	Microgram a measurement of weight equal to one millionth of a gram (or one thousandth of a milligram). Microgram (µg or mcg) is used for a number of nutrients found in food supplements.
Amino Acid	The building blocks of protein, there are eight essential amino acids which cannot be synthesised within the body and therefore must come from the diet. These are: isoleucine, leucine, lysine, methionine, phenylalanine, threonine, tryptophan and valine. In addition arginine and histidine are amino acids required by infants and young children which supports their rapid growth.
Antioxidant	A substance or nutrient which helps to protect our cells from damage caused by free radicals, damaging molecules which are found in pollution and tobacco smoke. Our bodies also produce free radicals as part of the normal biochemistry of living.
Deficiency	A lack of essential macronutrients or micronutrients which results in malnutrition and or disease. This may be the result of inadequate intakes or absorption issues associated with gastrointestinal disease. There are a number of recognised deficiency diseases including (but not exclusively): scurvy (vitamin C deficiency); rickets (vitamin D deficiency); anaemia (iron deficiency, but also deficiencies in B12 and folic acid) and Kwashiorkor (protein deficiency).
DH	The Department of Health is a UK Government department. It has responsibility for nutrition legislation and sets health policy for nutrition.
DHA	Docosahexaenoic acid; one of the key omega-3 fats that provides health benefits
Dietitian	An individual qualified in nutrition and dietetics who can assess, diagnose and treat health issues associated with nutrition and diet. Dietitians are governed by law with a statutory code of practice; they often work within the health service although increasing numbers are also working in a freelance capacity.
EFA	Essential fatty acids (omega 3 and omega 6) cannot be synthesised by the body and must be derived from the diet. EFAs do not provide fuel for energy production and are required for vital biological processes which support growth, development and health.
EFSA	European Food Safety Authority; the European Union food risk management agency which scientifically evaluates safety across all areas of food.
EPA	Eicosapentaenoic acid; one of the key omega-3 fats that provides health benefits.
Fat soluble vitamin	The fat soluble vitamins are vitamins A, D, E and K. Because they are fat soluble these substances can accumulate in the body, often being stored in fat cells, or in the liver. This can create health issues, particularly if intakes have been high for a prolonged period of time. For example, long term high intakes of vitamin D may lead to the laying down of calcium in tissues such as liver and kidneys which can cause nausea and vomiting.
Food supplement	A food supplement is a concentrated source of vitamins, minerals or other substances with a nutritional or physiological effect which is sold in small, measured unit doses.
FSA	The Food Standards Agency is a non-ministerial UK Government department responsible for food safety and food hygiene.
GLA	Gamma-linoleic acid is an omega-6 fatty acid (an essential fatty acid considered to be necessary for human health which must be derived from the diet). GLA is most commonly found in evening primrose oil (EPO), borage or starflower oil and blackcurrant seed oil.
Health claim	A health claim is any claim which states, or implies, that consumption of a specific food will have a beneficial effect on health. Claims may be written, verbal or pictorial.
Herbal medicine (herbal remedy)	A product is considered to be a herbal medicine if the main active ingredient/s are only herbal substances or preparations. Not all herbal products are medicines, some may be food supplements and some may be cosmetics. What determines if a product is, or is not a medicine is complex but generally rests with how the product is presented (i.e. does it make medicinal claims to treat, prevent or cure any disease) and what it does (i.e. does it have a physiological impact on, or alter, any body functions).
Macronutrient	Dietary constituents which are needed in significant amounts, generally protein, fat, carbohydrate, fibre and water.
Malnutrition	Malnutrition is a state in which the deficiency of nutrients such as energy, protein, vitamins or minerals results in measurable adverse effects on the body. Malnutrition may refer to insufficient intake of protein, carbohydrate and fats (macronutrients) which can result in overly low BMI. It may also be insufficient intake of vitamins, minerals and other micronutrients, which can impact on overall health and could include obese individuals with poor diets.
Mg	Milligram is a measurement of weight equal to one thousandth of a gram. Mg is used for a number of nutrients found in food supplements.
Micronutrient	A substance derived from food which is needed in extremely small amounts for the normal growth and development of living beings. Micronutrients are vitamins, minerals and essential fatty acids (omega-3 fats)
Mineral	Inorganic micronutrient essential to health and wellbeing. Minerals are absorbed from soil by plants which are in turn eaten by animals or humans. Minerals may be split into minerals which are needed in relatively high amounts (calcium, phosphorus, magnesium, sodium, chloride and potassium) and trace elements (iron, zinc, cobalt, copper, chromium, fluoride, iodine, manganese, molybdenum, boron and selenium) which are needed in very small quantities.
Multivitamin	A product which contains more than one vitamin, often multivitamins will contain all 13 vitamins although some may contain only the eight B vitamins, or a combination of some of the vitamins and some additional minerals.
NDNS	The UK National Diet and Nutrition Survey is a continuous rolling survey of the dietary habits and nutritional status of adults and children in the UK. The results are used to assess whether intakes of food and nutrients are adequate across different ages and population groups.
NRV	Nutrient Reference Value is the amount set by the European Food Safety Authority (EFSA), primarily to support food labelling, which the majority of the population requires to maintain health. Previously known as RDA
Nutrient	A substance derived from food which provides nourishment to the body and is essential for the maintenance of life and for growth and development.
Nutritionist	Nutritionists generally work for public bodies or governments, although some do work with private clients. They tend to look at large populations to determine risk factors and make dietary recommendations that are applied at population levels. For example, evidence on the incidence of type II Diabetes led public health nutritionists to determine that some populations are more at risk of developing this disease, and to make recommendations for dietary changes to either reduce the risk or manage the disease. However, public health nutritionists do not practice with individual patients.
Omega-3 fats	Essential fatty acids which cannot be synthesised by the body and must be derived from the diet. Primary sources for omega-3 fats are oily fish and fish oil supplements with some also coming from enriched eggs and fortified foods. There are a number of scientifically proven health benefits for omega-3 fats including supporting the health of the eyes, brain and heart, maintaining an appropriate balance of triglycerides in the blood and reducing blood pressure.
Omega-6 fats	Essential fatty acids which cannot be synthesised by the body and must be derived from the diet. Primary sources for omega-6 are vegetable oils such as sunflower and corn oils as well as nuts and seeds. There are a number of health benefits associated with omega-6 fatty acids; they are thought to be beneficial in the management of premenstrual syndrome and in some skin conditions including eczema and psoriasis.
PAGB	Proprietary Association of Great Britain (PAGB) is the UK trade association which represents the manufacturers of branded over-the-counter medicines, self care medical devices and food supplements.
Prebiotics	Foods which promote the growth of probiotics, the beneficial bacteria that inhabit our gut. Prebiotics are generally fibres such as inulin, which our bodies cannot digest and absorb but which provide a food source for probiotics.
Probiotics	Live bacteria (and some yeasts) which inhabit the digestive tract which are viewed as being beneficial to human health. There are thousands of different bacterial strains; some are resident in specific areas of the digestive tract whilst others are transient, simply passing through.
Public Health England (PHE)	Public Health England is an agency of the Department of Health responsible for improving public health. They work with local government, the NHS and non-governmental organisations as well as communicating public health messages to the general public.
PUFA	Polyunsaturated fatty acids (PUFA) are found in nuts, seeds, fish (and fish oil), krill and some algae, small amounts are also found in leafy greens. The omega-3 and omega 6 fats are PUFAs, which are generally associated with health.
RDA	Recommended Daily Amount; previously used terminology for the amount set, primarily to support food labelling, which the majority of the population require to maintain health. Now described using nutrient reference value (NRV)
SUL	Safe Upper Levels of vitamins and minerals were established by the Expert Group on Vitamins and Minerals who published a report in 2003 (https://cot.food.gov.uk/sites/default/files/cot/vitmin2003.pdf). The UK food supplements industry works to the levels set in this report.
Vitamin	Organic micronutrient essential to health and wellbeing. Vitamins cannot be synthesised in sufficient amounts by the animal or human body and must therefore be obtained from the diet. Plants manufacture vitamins which move up the food chain as the plants are consumed by animals or humans. Vitamins can be divided into fat soluble (vitamins A, D, E and K) and water soluble (vitamins B1, B2, B3, B5, B6, B12, biotin, folic acid and vitamin C).
Water soluble vitamin	The B vitamins and vitamin C are water soluble. They are not stored in any significant quantities within the body and are generally either utilised or excreted in the urine. As they are not stored in the body, they tend to have low toxicity and are needed on a daily basis.