This week's guest blog is from Lucy Walton, who has recently completed a BSc Nutrition and Psychology Joint Honours degree at Newcastle University and will be graduating at the end of July. Since completing her final exams Lucy has enjoyed getting creative with recipes in the kitchen and writing content for her Instagram page where she likes to share recipes, debunk nutrition myths and share practical nutrition tips and advice.
"I believe food is so much more than fuel and I am passionate about helping individuals to improve their health and relationship with food. I am excited to begin my career in nutrition and see where it takes me!"
Find Lucy on instagram
A plant-based diet is based on consuming foods and drinks which mainly come from plant sources including vegetables, fruit, wholegrains, legumes, nuts and seeds and limiting or avoiding animal products including meat, poultry, dairy, eggs and seafood. Plant-based diets can be placed on a spectrum from a vegan diet (no animal products consumed) to a flexitarian or semi-vegetarian (mainly following a vegetarian diet, but occasionally eating animal based products). Many different reasons exist for adopting these diets, three main motives include ethical reasons (concern about the treatment of animals), health purposes and environmental concerns.
Cutting animal-derived foods from the diet can eliminate intake of some essential vitamins and minerals, which could lead to deficiency. But a well-planned, plant-based diet which considers intakes of the following nutrients can be healthy and sustainable for many individuals.
Protein
It is often claimed that plant proteins don’t contain all 9 essential amino acids (the building blocks of protein). However, plant proteins do contain essential amino acids, they simply contain them in smaller quantities. Therefore combining different sources of plant protein and increasing quantities compared to portions of animal protein is recommended. This is not essential at every meal. If you are meeting your energy needs, your protein needs will also be met (1).
Plant sources: Beans, legumes and pulses, soya products such as tofu, beans, mince and unsweetened drinks, mycoprotein (Quorn products), nuts and seeds, plant-based yogurt alternatives.
Vitamin B12
Essential for the formation of blood, the function of the central nervous system and the function of cells in the human body, this vitamin is exclusively made by bacteria and only found in animal sourced food. Too little can lead to fatigue and nerve damage.
Plant sources: Can be found in small quantities in fortified products including breakfast cereals, plant-based drinks and yogurt alternatives, yeast extract spread and nutritional yeast. For vegans, a regular supplement (10mg daily) is preferable for surety (2).
Vitamin D
Often labelled the sunshine vitamin, as we get most of our intake of this vitamin from the sun. Vitamin D is essential for bone, immune and muscle health. In the winter months the sun is not strong enough to provide the required UVB rays to synthesise vitamin D in the skin. It is recommended in the UK that everyone supplements with vitamin D during these months (10mg)(3).
Plant sources: Fortified foods such as vegetable spreads and plant-based dairy alternatives. Sun or UV exposed mushrooms can also provide vitamin D.
Omega 3
Important for heart and brain health, this nutrient is found mainly in oily fish and fish oils. Long chain omega-3 polyunsaturated fatty acids are essential in the diet as they are not synthesised by the human body. However, research suggests vegetarians , vegans and non-fish eaters may not consume sufficient quantities of this nutrient (4).
Plant sources: Chia, hemp and flax seeds, walnuts, soybeans and soybean oil. If these foods are not usually consumed in your diet an EPA and DHA supplement from algae oil would be beneficial (200-300mg)(4).
Iron
This nutrient is well known for transporting oxygen around the body and storing oxygen in the muscles. Iron is also important for a healthy immune system and enzyme function. Haem iron, found only in animal products has a higher bioavailability (meaning a higher quantity of the nutrient is absorbed by the body) than non-haem iron, found in plant-based sources. Plant-based eaters should therefore ensure they are consuming sufficient plant-based sources of iron.
Plant sources: Green leafy vegetables (spinach, kale, watercress), wholegrains, dried fruit, tahini, nuts and seeds. Also found in some fortified breakfast cereals and yeast extract.
Calcium
Commonly known as the nutrient to help build strong bones, and rightly so, as calcium is important for bone development and health, blood clotting, teeth and muscle health. As this nutrient is found mainly in milk and dairy products as well as fish with bones, alternatives should be considered.
Plant sources: Kidney and soya beans, tofu, kale and broccoli. Calcium can also be found in some plant-based drinks and yogurt alternatives. Look for unsweetened versions and avoid organic as these cannot be fortified.
Iodine
Iodine is essential for function of the thyroid gland and brain, neurological development, reproductive health and fertility. The UK’s main source of this nutrient is milk and dairy products.
Plant sources: Plant-based drinks that are fortified with iodine, iodised salt, nori, seaweed (not recommended more than once per week as can provide excessive amounts of iodine). Vegan’s should consider a supplement (90mg per day)(5).
Zinc
This mineral is essential for immune health, digestion, taste and smell, wound healing and creating DNA and protein. Although zinc can be abundantly found in many plant foods, the bioavailability in plant-based sources is reduced (similar to iron).
Plant sources: Tofu, lentils, beans, hemp and pumpkin seeds, wholegrains, leafy vegetables, root vegetables, fermented soya such as tempeh and miso and fortified breakfast cereals.
Selenium
Selenium provides the body with antioxidants and is important for DNA production, reproduction and thyroid health. Attention to intake should be considered as consumption of eggs and fish provide large proportions of selenium needs.
Plant sources: Wholegrains, nuts and seeds, 2 brazil nuts per day will provide you with your daily requirement of selenium(2).
Conclusion
Overall, a balanced plant-based diet which includes varied sources of protein, carbohydrates, vegetables and healthy fats can support healthy living throughout the life course. Supplementing with some nutrients such as vitamin D, B12, iodine and essential fatty acids may be needed, this should be considered on an individual case-by-case basis. Fortified foods may also be beneficial to include to ensure needs are being met. Are you considering adopting a plant-based diet? Or if you already follow a plant-based diet, where do you get your nutrients from?
References
1. Melina et al. (2016) “Position of the Academy of Nutrition and Dietetics: Vegetarian Diets” [Available via: https://jandonline.org/article/S2212-2672(16)31192-3/abstract]
2. BDA Food Fact Sheet ‘Plant-based diet’ [Accessed 02/07/2020 via https://www.bda.uk.com/resource/plant-based-diet.html]
3. Scientific Advisory Committee on Nutrition. Vitamin D and Health Report. (2016) [Available via https://www.gov.uk/government/publications/sacn-vitamin-d-and-health-report]
4. Lane et al. (2014) “Bioavailability and Potential Uses of Vegetarian Sources of omega-3 Fatty Acids: A Review of the Literature [Available via: https://pubmed.ncbi.nlm.nih.gov/24261532/]
5. Messina G. (2010) Recommended Supplements for Vegans [Accessed 02/07/2020 via https://www.theveganrd.com/2010/11/recommended-supplements-for-vegans/