Plant-based nutrition – a good lifestyle choice?
Many people are opting for plant-based diets but are they as healthy as people think?
The short answer is yes!
Plant-based diets have been shown to prevent and even reverse some chronic diseases. But they can be restrictive, and it’s possible to fall short of some key nutrients (we’ll get to that). However, with careful planning and support from a qualified nutritionist (hello!) they can be healthy, nutritionally adequate, and suitable for anyone.
Why is ‘plant-based’ becoming so popular?
Plant-based is one of the top three global food trends as of 2020. People are choosing plant-based eating for a variety of reasons: sustainability, animal welfare, religious beliefs, and/or personal preference. Plus, there are loads of potential health benefits: plant-based diets are associated with weight loss, reduced risk of mortality, and lower risk of heart disease. They are also linked to the prevention and treatment of hypertension, high cholesterol, and a reduced risk of cancer.
These days it has never been easier to go plant-based; there are increasingly more plant-based alternatives to dairy, meat, condiments, and treats on the supermarket shelves. More restaurants are expanding their vegan or vegetarian options. You can even get most of your favourite fast food items completely animal-free. Tread carefully though, as some plant-based alternatives may rely on increased fat, sodium, sugar, and additives to improve their taste or texture. Indulging in the less healthy options too frequently will most likely not lead to the health benefits plant-based diets are known for.
Celebrating plants in our diet
If you are considering going plant-based, remember too there are plenty of ways to include more plants in your diet without eliminating meat or dairy from your diet entirely. Vegans eat only plant-based foods, but vegetarians include dairy and eggs, and pescatarians/flexitarians eat mainly plant-based but also consume small amounts of fish or meat.
Some key nutrients you should retain in your diet
Many of the nutrients that we need come from animal sources, as do many supplements (e.g., collagen). The challenge for vegans, especially, is to ensure they get enough of these key nutrients in their daily diet. This is by no means a complete list of nutrients to look out for, but let’s take a look at some examples:
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Vitamin B12 - required for production of DNA, red blood cells and nerve cells.
B12 is only found naturally from animal sources, so vegans should eat fortified foods such as marmite or nutritional yeast, and/or take a B12 supplement. Mushrooms contain a very small amount of B12, and tempeh may be a source, although an unreliable one. Vegetarians get B12 from dairy products and eggs.
Iron – essential for red blood cells to transport oxygen around the body.
There are two types of iron. The richest dietary source, and best-absorbed by our bodies is ‘heme’ iron, found in animal foods. ‘Non-heme’ iron comes from plants; good sources include legumes, grains, nuts, seeds, and fortified cereals. Unfortunately non-heme iron isn’t as well absorbed as heme iron, but it’s possible to improve that absorption by eating those foods with foods containing vitamin C. This is especially important for menstruating women and athletes.
Zinc – an antioxidant essential for metabolism, immunity, and reproductive health.
Plants do contain zinc, but in smaller quantities than animal sources. Good plant sources of zinc include legumes, soy, nuts, seeds, wholegrains, and fortified foods. However, zinc from plants is harder for the body to absorb due to the presence of phytic acid, but soaking, sprouting, fermenting, or heating will improve absorption.
Omega 3 fatty acids - reduce inflammation and maintain heart, brain, eye, and skin health.
The most well-known and consumed sources of omega 3 are fatty fish and fish oil supplements. They contain eicosapentaenoic acid (EPA), and docosahexaenoic acid (DHA) which are the most beneficial for health. Some plant foods such as walnut, flax, chia, canola, hemp seeds and their oils contain another omega 3 fatty acid: alpha-linolenic acid (ALA). This omega 3 is converted to EPA and DHA in the body, but the process is very inefficient, and intake of ALA alone may not be sufficient for adequate omega 3 status. Therefore vegans should consider a plant based source of EPA and DHA such as micro-algal oils.
Vitamin A – essential for eye health, immunity, and development.
Active vitamin A, called retinol, is only found in animal foods, or foods fortified with vitamin A such as plant-based milks or margarine. Another source of vitamin A in the diet is from plants containing beta-carotene, which your body converts into retinol. Foods rich in beta-carotene include kumara, carrots, pumpkin, red capsicum, melon, and leafy greens. It’s important to incorporate a variety of these foods in the diet every day to ensure adequate vitamin A status. Pro tip: combining a fat source to foods containing beta carotene can increase absorption in the body.
Iodine – essential for healthy thyroid function (controls metabolism, growth and development).
Many New Zealanders are low in iodine – our soil has low levels of it, so veggies that are usually high in iodine, aren’t. The main sources of iodine here are fish, seaweed, eggs, and dairy, although most commercially produced bread contains iodine (due to the required use of iodised salt in baking). Vegans must include a regular intake of fortified bread, sea vegetables, and use iodised salt in cooking for adequate iodine status.
Hydroxyproline – a key component of the protein collagen.
Not exactly classed as an essential part of the diet, but for the support of healthy skin and joints, consuming collagen (either supplements or from gelatinous meat or bone broth) helps boost natural collagen production in the body. Hydroxyproline is an amino acid found only in collagen, and, interestingly, minute amounts in alfalfa sprouts. It is classed as non-essential because it can be converted in the body from another amino acid, proline, with vitamin C as a cofactor. But this places a greater demand on dietary sources of proline, of which small amounts can be found in cabbage, beans, asparagus, and soy. To support optimal collagen production in the body, vegans should ensure their diet is high in proline-rich foods, and the nutrients needed for hydroxyproline formation such as vitamin C, zinc, and copper.
