Major New Health Report Warns Of Nutritional Shortfalls With Plant-Based Diets

A new report[1] from the Health and Food Supplements Information Service (HSIS) reveals that the adoption of plant-based diets could result in a serious lack of vitamins, minerals and omega-3 fats in the diet, with worrying health consequences including a shortening of life expectancy.

The report, Plant Based Diets: Nutritional Challenges and Future Health Worries – An A-Z Analysis, reviewed data from 101 published studies, comprising of a total of 17,262 people, looking at the growing trend for plant-based diets and how this dietary choice is impacting nutrient intakes. In addition, a consumer omnibus was conducted to assess people’s dietary habits, understanding and views.

This latest HSIS report found that people on plant-based diets, vegans and vegetarians are typically at risk of dietary shortfalls for optimal wellbeing and health as well as undermining their micronutrient status which helps fuel health and wellbeing daily including seven key nutrients; Vitamin B12, vitamin D, Iron, Zinc, Iodine, Selenium, and Omega-3 fats.

Several of these nutrients such as iron, zinc and selenium are known to support normal immune function, essential for health and wellbeing, and particularly relevant at this time. While iodine and iron are important for supporting cognitive function, Vitamin D is key for optimal bone health, and omega-3 fats are vital for protecting the heart and brain. Chronically low levels of iron and B vitamins can also lead to tiredness and fatigue.

The HSIS consumer research also found that people who adopt plant-based diets often don’t do their research before switching to a plant-based diet, and this could be a key explanation for the low nutrient intakes seen across many international dietary surveys.

Consumer research findings

The HSIS consumer research revealed that a quarter of vegans and vegetarians say they had been diagnosed with a nutrient deficiency at some stage, mostly related to iron or vitamin D.

Hints of dietary problems are evident in the study with a quarter of people experiencing tiredness even after a good night’s sleep, and a fifth reporting depression. Low levels of B vitamins have been linked with these issues.

One quarter (25 per cent) report having dry skin while one in ten complained of hair loss or brittle nails. Vitamin A, zinc and selenium are all essential for the integrity of the hair and nails, and there are lower levels of these nutrients in plant-based diets.

Co-author of the report^,GP, Dr Nisa Aslam, commented: “Awareness of nutrient shortfalls is very low, with HSIS research showing that fewer than a fifth of plant-based adherents identifying vitamin B12 as an issue, and no-one name-checking vitamin D despite the fact that nearly all major dietary sources of the ‘sunshine vitamin’ are animal or fish based. Awareness of other nutrients that are hard to obtain on plant-based diets; zinc, iodine and selenium is almost non-existent. That’s why taking a multivitamin and multimineral supplement is so vital.”

Co-author, nutritionist and adviser to HSIS, Dr Emma Derbyshire added: “With poor planning and research, and a worryingly low awareness of key nutrients, it’s really important that people who are thinking of switching to a vegan, vegetarian, flexitarian, plant-based diet or even those who are cutting out food groups should incorporate a daily multinutrient supplement into their diets.

“This can help make up nutrient shortfalls and ensure that people are more likely to meet their vitamin and mineral requirements. For those who avoid fish, an algae-based omega-3 supplement is also recommended since the particular omega-3 fats found in oily fish – called EPA and DHA – don’t exist in plant foods.”

Plant-based diet trend

A record 400,000 people worldwide signed up to Veganuary this year, and it’s been estimated that vegans and vegetarians will make up a quarter of the UK’s population by 2025[2]. Concern about nutrient gaps in plant-based diets is heightened given the recent surge in consumers ditching meat and dairy products.

Talking about the report finding, Dr Gill Jenkins, GP said: “Thousands more people are taking up plant-based diets, but a lack of planning often means they are risking deficiencies of key nutrients. Only a fifth of people are currently take a multivitamin or vitamin D – despite today’s stronger messages about topping up on vitamin D. Our advice would be – if you are vegan or vegetarian, or considering a plant-based diet, you should plan to take a daily multinutrient supplement plus a vegan source of omega-3s. And the same goes for those people cutting out food groups or indeed on a weight loss plan.”

Notes to Editors

Key nutrient deficiencies for those following plant-based diets

Vitamin B12: Helps to metabolise energy and homocysteine, maintain a healthy nervous system, red blood cell formation, immune function, cell division as well as reducing tiredness and fatigue.
Vitamin D: Helps absorption/utilisation of calcium and phosphorus and blood calcium levels, as well as maintaining normal bone, teeth, muscle and immune function.
Iron: Contributes to normal energy metabolism, cognitive function, formation of red blood cells and haemoglobin, oxygen transport in the body and the reduction of tiredness and fatigue.
Zinc: An important part of many enzymes, some of which have key roles in tissue growth, zinc is essential for fertility and reproduction. It helps the growth of immune cells and the body to produce its own antioxidant enzymes, as well as helping to keep hair, skin and nails healthy.
Iodine: Essential for the manufacture of thyroid hormones, needed for normal growth and development, especially of the brain and central nervous system. Contributes to function of the immune system and helps keep skin healthy.
Selenium: Contributes to sperm formation, is important for thyroid function, immunity, protecting cells from oxidative stress and inflammation, as well as helping to keep hair and nails healthy.
Omega-3 fats: Omega-3 fats are essential fatty acids – eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). EPA and DHA are found in every cell membrane in the body and have a wide range of functions including helping to reduce triglyceride[3] levels in the blood; heart health; supporting brain function; helping to reduce blood pressure and helping to maintain eye health. EPA and DHA also inhibit the production of inflammatory chemicals in the body and have an anti-inflammatory effect in their own right. DHA is important in infant development, particularly in prematurely born infants. It is believed to be necessary to early eye and brain development. DHA is also thought to support brain development throughout childhood.

What is a plant-based diet?

The British Dietetic Association (BDA) defines a plant-based diet as one “based on foods derived from plants, including vegetables, wholegrains, legumes, nuts, seeds and fruits, with few or no animal products”.^[4] Other ‘official’ definitions can be found in Table 1. Key to the BDA definition is that it simply spells out plant based in an uncomplicated way. The definition also clearly states that the plant-based diet can be devoid of animal products or can contain a few.

Table 1: Definitions of plant-based diets.

*British Dietetic Association (2020)*	“A plant-based diet is based on foods derived from plants, including vegetables, wholegrains, legumes, nuts, seeds and fruits, with few or no animal products”.
*EAT-Lancet Commission (2019)*	“The volume of approximately half a plate should be vegetables and fruits whilst the other half should consist of primarily whole grains, plant protein sources, unsaturated plant oils, and (optionally) modest amounts of animal sources of protein.”
*McManus (2018) Harvard Medical School*	“Plant-based or plant-forward eating patterns focus on foods primarily from plants. This includes not only fruits and vegetables, but also nuts, seeds, oils, whole grains, legumes, and beans. It doesn’t mean that you are vegetarian or vegan and never eat meat or dairy. Rather, you are proportionately choosing more of your foods from plant sources”.
*Tuso et al. (2013) Definition for Physicians*	“A regimen that encourages whole, plant-based foods and discourages meats, dairy products, and eggs as well as all refined and processed foods.”

What does plant-based eating look like?

People in the HSIS research study reflected the variety of opinion and practice. There are no right and wrong answers. A plant-based is not necessarily vegan or vegetarian though it may be. And it may indeed be flexitarian, perhaps eating animal source foods at some times and not at others whilst including lots of fruit and vegetables, beans, grains and so on.

A plant-based diet may contain fish in which case it is often referred to as pescatarian. A vegetarian diet would include dairy and eggs whilst a vegan diet would cut out all animal derived products, including meat, fish, dairy, eggs, honey and gelatine.

[1] Plant Based Diets – Nutritional Challenges and Future Health Worries – An A-Z Analysis; authored by Professor Robert Pickard, Dr Emma Derbyshire, Dr Gill Jenkins, Dr Nisa Aslam, Dr Pamela Mason; ahead of publication – summer 2020

[2] Future of Food report 2019

[3] High triglyceride levels cause health risks such as atherosclerosis, coronary artery disease and stroke

[4] https://www.bda.uk.com/resource/plant-based-diet.html

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.