What's Missing In Your Vegan And Vegetarian Diet?
In the past 10 years, vegetarian and vegan diets have become increasingly more popular. Although there are several health benefits associated with eating a plant-based diet (higher fibre, vitamin C and E, minerals and phytonutrients) there is also an increased risk for nutritional deficiencies.1
Protein is essential in our diet. The body is mostly made up of protein through many combinations of 20 different amino acids. Proteins play several different roles in the body, creating hair, skin, nails, organ regeneration, muscle tissue, enzymes for reactions occurring in the body, etc.
Getting enough protein in the diet is entirely possible on a vegan or vegetarian diet, it just takes more of an effort to track consumption and to ensure you’re eating a varied diet.
Suggested protein intake varies from person to person as optimal intake depends on weight, activity levels, and goals. A general rule to follow to ensure adequate protein intake is about 0.6-1g of protein for every pound of body weight.2,3 For example, if someone weighs 120 lbs, their protein intake would be about 72 -120g of protein per day. If you are more sedentary and looking to maintain weight, you would be on the smaller end range. If your goal is to increase muscle mass or you are an active person, it will be closer to the 1g per pound. If you are highly active and looking to gain muscle mass, you may be above 1g per lb.3 It’s always good to check in with a health care practitioner to help assess your individual needs.
Some good plant-based sources of protein include: black beans, lentils, chickpeas, tofu, split peas, almonds, hemp seeds, pumpkin seeds and some grains such as steel cut oats and spelt. Adding in a whey (vegetarian) or plant-based (vegan) protein powder into smoothies can be helpful way to increase protein.
Omega-3 fatty acids-
Another common deficiency found more frequently in vegans and vegetarians is omega-3 fatty acids.1 Omega-3 fatty acids (EPA and DHA) can be produced in the body from essential fatty acids (linoleic and alpha-linolenic acid) however the process is highly inefficient. Therefore, we call omega-3 fatty acids conditionally essential, meaning it is best to get these through the diet.
Omega-6 fatty acids, another type of polyunsaturated fatty acid, are usually sufficient in both vegan and vegetarian diets. However, the ratio of omega-6 to the amount of omega-3 fatty acids is much too high. Hence, an emphasis should be put on increasing consumption of more EPA and DHA in the diet. Omega-3 fatty acids assist in decreasing inflammation in the body which plays a key role in most chronic disease.4
Omega-3 fatty acid consumption is difficult for vegans and vegetarians because the best sources come from fish. Nuts and seeds have alpha-linolenic acid, but as mentioned earlier this type of polyunsaturated fat has a poor conversion rate to EPA and DHA which are the anti-inflammatory forms of omega-3’s used in the body. The best way for a vegan or vegetarian to consume adequate amounts of omega-3 fatty acids is through an algae oil. Algae oil is the only plant-based source of EPA and DHA.5
B12 for the most part is found in animal products; therefore, low levels are commonly found in vegans and in some vegetarians.1 Low B12 levels can lead to nerve damage, fatigue, depression, and weakness. Now, many foods are fortified with B12 (most plant milks, cereals, and tofu) so there is a possibility that B12 supplementation is not needed. However, most vegans will need a B12 supplement to obtain adequate levels. It is important to have B12 levels checked by your healthcare practitioner.
For vegetarians, B12 can be found in dairy products and eggs. Shiitake mushrooms also contain B12.
Iron intake is usually on par or higher in vegan and vegetarians due to the increased intake of plan-based iron, called non-heme iron. Though, it’s important to note that heme iron which comes from animal products such as beef, chicken or fish is much more absorbable. Iron deficiency is not markedly decreased in vegans and vegetarians when compared to omnivores, however, in general 30% of women have iron deficiency anemia globally (omnivores or vegan).6 Therefore, it’s important for all populations to consider their intake of iron. If you are vegan or vegetarian, it will take a higher amount of iron to acquire to adequate levels due to the decreased absorption.
Good plant-based sources of iron include leafy greens, seeds, legumes, nuts, whole grains, apricots, and figs. Iron is better absorbed when taken with vitamin C. Therefore, eating an orange with your nuts or putting some lemon on your salad with leafy greens can increase absorption.
Iron levels should be tested by your healthcare practitioner if you are vegan or vegetarian and think you may be deficient. This is especially important for menstruating women.
Lower vitamin D levels are reported more often in vegan populations as the best sources are found in animal products such as fish, red meat, organ meat and eggs.1 Some vegan foods (cereals, orange juice, plant-based milks) are fortified with vitamin D but most vegans and vegetarians will struggle to meet adequate vitamin D levels in the winter months without supplementation.
Becoming vegan or vegetarian can be done healthily, it just takes some time to get used to. Tracking calories and protein intake along with appropriate testing, monitoring and supplementing key vitamins and minerals is the best way to keep your health on track while following a vegan or vegetarian diet.
It is always best to see a healthcare practitioner when switching your diet or if you have been on a restricted diet for a while and think you may be deficient.
- Craig WJ. Health effects of vegan diets. The American journal of clinical nutrition. 2009 May 1;89(5):1627S-33S.
- Tang M, McCabe GP, Elango R, Pencharz PB, Ball RO, Campbell WW. Assessment of protein requirement in octogenarian women with use of the indicator amino acid oxidation technique. The American journal of clinical nutrition. 2014 Apr 1;99(4):891-8.
- Bray GA, Smith SR, de Jonge L, Xie H, Rood J, Martin CK, Most M, Brock C, Mancuso S, Redman LM. Effect of dietary protein content on weight gain, energy expenditure, and body composition during overeating: a randomized controlled trial. Jama. 2012 Jan 4;307(1):47-55.
- Li K, Huang T, Zheng J, Wu K, Li D. Effect of marine-derived n-3 polyunsaturated fatty acids on C-reactive protein, interleukin 6 and tumor necrosis factor α: a meta-analysis. PloS one. 2014 Feb 5;9(2):e88103.
- Lane K, Derbyshire E, Li W, Brennan C. Bioavailability and potential uses of vegetarian sources of omega-3 fatty acids: a review of the literature. Critical reviews in food science and nutrition. 2014 Jan 1;54(5):572-9.
- World Health Organization. Global anaemia prevalence and number of individuals affected. Reference Source. 2008.