What you need in a vegan diet

Are you doing Veganuary this year?

I am not an advocate for diets and I don’t really like putting labels on the way we eat but one thing we know for sure is that eating more plant-based foods has enormous health benefits.

I was vegan for over 2 years but after gaining more knowledge about my own health and nutrition, I decided it was right for me to eat eggs and fish again. I still avoid dairy because it is inflammatory and it doesn’t agree with me (I have inflammatory bowel disease). I support vegan clients in my clinic and we always work together to make sure they’re not missing out on important nutrients.

If you are vegan or just trying it in January, here are a few things to consider so you don’t end up with nutritional deficiencies.

First of all, let’s recap - what exactly is a vegan diet?

Vegans exclude all animal products, including meat, eggs, dairy and honey. It is purely based on a plant food diet with vegetables, grains, pulses, legumes, fruits, nuts, seeds and vegetable fats.

So now let’s focus on the nutrients you should look for:

PROTEINS

The Recommended Dietary Allowance (RDA) is 0.8 grams per kilogram of body weight. This can be difficult to achieve on a plant-based diet but not impossible if you make sure to have protein at every meal including breakfast and snacks! Some good food sources are tofu, tempeh, nuts and seeds, lentils, quinoa, millet and buckwheat.

Our living cells depend on proteins; their monomer is amino acids and the cells cannot manufacture nine of them. They are called essentials as they can only be found in the diet. Animal proteins have a better balance of essential amino acids and are complete proteins (1).

Most plant-based foods are not complete proteins unless they are combined. Lysine and isoleucine are the limiting amino acids in grains, nuts and seeds whereas methionine and tryptophan are the limiting amino acids in legumes. Therefore, it is recommended to combine various sources such as grains and legumes (2). For instance, lentil corn and quinoa salad, peanut butter on oatcakes or hummus with seed loaf could be meal ideas for vegans to achieve a complete protein and increase the amount of utilisable protein.

 LIPIDS

 Fats, or ‘lipids’, are sources of long-term energy for the body. They provide insulation, make up cell membranes and are structural components of the brain.

There are also some essential fatty acids (EFA) required in the diet, namely linoleic acid, an Omega-6 fat (LA) and alpha-linolenic acid, an Omega-3 fat (ALA). The vegan society explains that the right intake of LA can be achieved through a varied, balanced diet with for instance hemp seeds, pumpkin seeds, sunflower seeds and soya spread (3).

However, having enough ALA can be challenging and necessitate more planning to achieve optimum nutrition.

The best source of omega 3 is oily fish. Chia seeds and ground linseed are also good plant-based sources of omega 3 - a tablespoon of chia seeds could cover the RDA.

Other fats such as eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), a long-chain Omega-3 fat, are also beneficial although not EFA. It was shown that vegan diets are generally lacking EPA and DHA, as the main source of this is oily fish.  A direct plant source is microalgae oil, through which fish acquire them. The vegan society favors supplementation of EFA from microalgae, as Omega-3 is essential for brain health (3).  

IRON

Vegans should get all the iron needed from a varied diet (pulses, beans, cereals, nuts and fruits) but plant-based foods are less bioavailable than iron from animal sources. In order to aid iron absorption, vitamin C rich food should be eaten at the same time as iron rich food (4). For instance, tomatoes with tofu or kiwi and sunflower seeds are good combinations. Drinking coffee and tea away from your meals is also important as this can reduce absorption.

ZINC

 Zinc is essential for growth and development. Content in plant-based foods such as lentils, cashews and soy is generally much lower than animal sources and also has lower bioavailability because of their phytate content (5). Soaking, leavening or fermenting are some preparation methods that improve absorption (4).  

VITAMIN B12

 B12 is the only nutrient not directly available from plants and therefore vegans are at risk of deficiency (5). Therefore supplementation is recommended for all vegans. On top of that, I would recommend consuming yeast extract, nutritional yeast or fortified plant milks on a regular basis to increase B12 in your diet.

 IODINE & SELENIUM

Good plant-based sources are seaweed and iodised salt (1).

Iodine supplementation is recommended to ensure the optimum level as plant sources are unreliable, even seaweed  (5). Deficiency could lead to insufficient amounts of thyroid hormone, which you need to control your metabolism. Iodine needs to be supplemented very carefully as your thyroid also doesn’t want too much of it!

Selenium is also an important mineral for thyroid health. Two Brazil nuts daily could optimise your selenium status but make sure you don’t eat too many of them!

Thyroid health is very complex so if you have a hormonal imbalance or a thyroid disorder, I would suggest you consult a registered nutritionist before supplementing with these two important minerals.  

 CALCIUM

Calcium is essential for your bones and teeth and is key in the activity of many enzymes in the body.

But good news, Milk isn’t the only source of calcium – far from it! Plant-based foods are rich in calcium including almonds, sesame seeds, tofu, kale, watercress and apricots. However, it can be hard to reach the RDA so buy fortified products as much as possible (e.g. plant-based milk).

Bear in mind that vitamin D helps absorb calcium so read the below carefully!

VITAMIN D

This isn’t just a nutrient of concern for vegans. Being the only nutrient that comes from the sun, it is difficult for anyone to get the RDA from food (6). The NHS recommends a supplement from October to March but some people could benefit from Vitamin D for longer.

Most people would benefit from a 1,000 to 2,000 IU (25 µg to 50 µg) daily but make sure you don’t take more than you need and that you take the right dose depending on your lifestyle and health conditions. Get tested if you can!

To sum-up, a plant-based diet is nutritionally safe for most people when it is well planned and supplemented and when it doesn’t focus on vegan junk foods. Beware of the fake cheese and the highly processed vegan sausages. Choose whole foods and try to cook your meal from scratch as much as possible.

References

1. Murray M and Pizzorno J (2008) The Encyclopaedia of Healing Foods. London, Piatkus Books.

2. Nhs.uk. (2015). The vegan diet - Live Well - NHS Choices. [online] Available at: https://www.nhs.uk/Livewell/Vegetarianhealth/Pages/Vegandiets.aspx

3. The Vegan Society. (2017). Omega-3 and omega-6 fats. [online] Available at: https://www.vegansociety.com/resources/nutrition-and-health/nutrients/omega-3-and-omega-6-fats

4. The Vegan Society. (2017). Iron. [online] Available at: https://www.vegansociety.com/resources/nutrition-and-health/nutrients/iron

5. Hever, J and Cronise R.J., (2017). Plant-based nutrition for healthcare professionals: implementing diet as a primary modality in the prevention and treatment of chronic disease. - PubMed - NCBI. [online] Ncbi.nlm.nih.gov. Available at: https://www.ncbi.nlm.nih.gov/pubmed/28630615

6. Lipski, E. (2020) Digestive Wellness, 5th Edition, McGraw Hill