Plant-based diets: are they optimal for health?
For a long time now nutrition science has supported the notion that we should be eating more plants. Plant foods include fruits, vegetables, grains, legumes, beans, nuts, and seeds. From the vitamins and minerals that plants contain to the disease-fighting polyphenols, there is just no substitute when it comes to our health for a diet rich in plant foods. This is combined with our more recent knowledge about the vast benefits of dietary fibre for our gastrointestinal health and gut microbiome. We know that eating more plants can help us feel and perform our best.
Do our diets need to be exclusively plant-based?
However, it is also true that as humans we’ve evolved as omnivores. This means we require a wide variety of nutrients from a large number of foods to meet our needs. This includes foods that come from both plants and animals. What is interesting though is that all essential nutrients can be found in whole, unprocessed plant foods. There is however, one exception.
So if essential nutrients are so abundant in plant-based diets, why might vegans run into nutrition trouble?
In a word: convenience. A lot of very nutritious plant foods are not particularly fast or easy to prepare. Things like dried beans, whole grain brown rice, or sprouted grains. Many of the most nutrient-dense plant foods have their nutrients locked up tight inside the cell walls. This means we need to soak, cook, or sprout them in order to be able to reap the benefits. Who’s got time for that?
Most of us have limited time to cook, so we rely on convenience foods to get us through the day. Unfortunately, many of these foods don’t provide us with the same quality nutrition that we get from whole, home-cooked foods. For example, Oreo cookies, soda, and potato chips are all vegan, but they certainly aren’t the best food choices in terms of nutrition! If we only focus on whether or not a food contains animal products we can wind up eating a whole lotta refined carbs, but not much else.
Key Nutrients Plant-Based Eaters Should Be Aware Of
Which nutrients might you be missing if your plant-based diet is consisting of too many packaged foods, sweetened beverages, and skip the dishes orders? Read on to find out!
Best plant-based sources: tofu (and other soy foods), lentils, beans, whole grains, quinoa, nuts and seeds.
While there is no shortage of plant-based protein sources, it may require some effort and planning to consume enough due to long cooking times and preparation. It can also be challenging to find high protein convenience foods that don’t contain a lot of added sugars or artificial ingredients. If you’re an athlete, not eating enough protein can cause a slump in performance and difficulty building muscle, so protein should be a priority when creating a plant-based meal plan.
Tip: Make high-protein plant foods part of every meal and snack. When choosing new recipes make sure they include a good source of protein, or pair it with a high-protein food.
Best plant-based sources: beans, lentils, nuts and seeds, tofu, cooked spinach, asparagus, beets and beet greens.
In the digestive tract, iron is not as readily absorbed by our bodies as some other nutrients. Iron is also naturally found in different forms in different food sources. Heme iron comes from animal foods (such as red meat or poultry), and is similar to the form of iron that is found in our bodies. Non-heme iron on the other hand is the type of iron found in plant sources. Non-heme iron is bound by natural substances that make it harder for us to access, so even if we are choosing iron-rich foods we may not have adequate iron levels in our bodies.
Iron is important for helping the body carry oxygen through the blood to our cells, so if we have low iron levels we may feel tired, irritable and low in energy. Genetics also play a role here. Some people do not absorb iron as well as others, so they may be at an even higher risk for iron-deficiency if they do not consume meat.
Tip: Pair up sources of iron with foods rich in vitamin C. Vitamin C helps to increase the absorption of iron by changing it to a more readily-absorbed version. If you need to take iron supplements despite choosing iron-rich plant foods, be sure to take it with a source of vitamin C, and avoid taking it at the same time as any calcium or zinc-containing foods or supplements.
Best plant-based sources: Wheat germ cereals, bran cereals, nuts and seeds, tempeh, tofu, beans and lentils.
Zinc is an important nutrient for the body’s growth and immune function. Without enough zinc in our bodies we may get sick more often, have trouble healing, or lose our appetite.
Tip: The zinc in plant foods is often bound by phytates, which are natural compounds that prevent us from absorbing zinc in the digestive tract. Cooking techniques like soaking beans, sprouting grains, or leavening bread dough improves zinc’s bioavailability. Choosing whole grains and/or sprouted grain foods is a great way to get more zinc.
Best plant-based sources: There are no natural vegan sources of vitamin B12.
Foods commonly fortified with vitamin B12 include nutritional yeast, plant-based milks, or soy products.
Vitamin B12 plays a key role in our cells energy metabolism. Without adequate vitamin B12 we can feel weak, fatigued, and have poor exercise tolerance. Our personal genetics can also dictate how well we absorb vitamin B12 from the foods you eat. The stomach produces a substance called ‘Intrinsic Factor’, which is critical for the absorption of vitamin B12. This Intrinsic Factor (IF) binds to the vitamin B12 in the stomach, and carries it into the small intestine where it helps it to be absorbed. Some people produce very little IF (levels also tend to decline as we age), so even if a person consumed very large amounts of B12, their blood levels can remain too low.
Tip: Get your vitamin B12 level checked regularly to avoid a deficiency. Because some people do not absorb vitamin B12 very well, so supplementation may be necessary even if you consume fortified foods regularly. Some medications can also interfere with vitamin B12 absorption in the body, so it is important to talk to your Doctor about your vitamin B12 status.
Best plant-based sources: Mushrooms, fortified plant milks (and other fortified foods)
Vitamin D plays a key role in bone health, immunity, and reduction of inflammation in the body. Vitamin D is a unique nutrient because it acts very similarly to a hormone in our bodies. This means that it is involved in many complex and important bodily functions, and does a number of jobs in our bodies that keep us healthy. Newer research is also looking at the link between vitamin D levels and things like mental health, mood, and chronic disease. So vitamin D is absolutely key for good health!
We actually make vitamin D when we are exposed to sunlight, but in the northern hemisphere during the winter it can be nearly impossible to achieve the sunlight exposure needed to keep our vitamin D levels high enough. Vitamin D is not naturally abundant in our food supply, so many of us can wind up with blood levels that are too low.
Tip: It is recommended in Canada to take a Vitamin D supplement to ensure adequate levels in the body year-round.
Best plant-based sources: Cooked greens (spinach, kale, turnip greens), almonds, white/navy beans, or foods fortified with calcium including tofu, breakfast cereals, orange juice, and plant-based milks
As we all know calcium is a key nutrient for the formation of strong, healthy bones. But, did you now that calcium is also important for many other body functions including muscle contractions? And not just our biceps and triceps. The heart is a muscle too, so calcium is involved in the regulation of each and every heart beat. Because keeping our heart beating is pretty much the most important thing our body has to do in a day, if we aren’t eating enough calcium in our diet, the body will sacrifice calcium from our bones in order to keep us functioning properly. Chronic low calcium intake can contribute to poor bone health and conditions like osteoporosis. Fortunately, there are many sources of calcium available for plant-based eaters including both plant foods and fortified foods.
Tip: Always choose fortified plant-based milks to replace dairy. Vitamin D also increases calcium absorption in the digestive tract so getting enough vitamin D in your diet is key for optimizing your calcium intake.
Riboflavin (Vitamin B2)
Best plant-based sources: spinach, soy, mushrooms, almonds, fortified grain products and cereals
Riboflavin is another one of the B vitamins that is important for energy metabolism (the body’s ability to turn the food we eat into energy in our cells), among many other important body functions. Because riboflavin is naturally found in more animal-based foods than plant foods, a lot of grain products we buy at the store have been fortified with additional riboflavin. If you’re an athletes you actually have a higher need for riboflavin than sedentary people, so including plant-based sources of riboflavin each day is critical for good health and performance.
Tip: Some bacteria that live in the digestive tract produce riboflavin during digestion, which our bodies can absorb and use. A high-fibre diet can help increase the riboflavin these bacteria produce. Just one more reason to eat more plants!
Omega-3 fats (EPA/DHA)
Best plant sources: Seaweed and algae (generally taken as a supplement)
EPA and DHA are omega-3 fats that we typically get from fatty fish in our diet. Interestingly though, the fish themselves get their omega-3 fats from eating plants that produce them! So, plant-based eaters who avoid fish can actually get EPA and DHA from plant-based supplements.
Other omega-3 fats can be found in plant foods such as nuts, seeds, and canola oil
Looking for a plant-based EPA/DHA supplement? This brand tastes great and provides 1000mg of EPA/DHA per serving! Please note if you make a purchase through this link I will receive a small commission at no extra cost to you
Best plant sources: Soy, potatoes, wheat germ, quinoa, kidney beans
Choline is an important nutrient that plays a role in numerous body functions. Because choline is involved in so many steps in our metabolism, almost every body system relies on choline. Animal foods (meat, eggs, fish, dairy) contain some of the highest amounts of choline per serving, but a wide variety of plant foods contain some as well.
Tip: Include a variety of choline-rich plant foods in your diet each day, and avoid filling up on highly refined or processed foods. Choose meat alternatives regularly like tofu and kidney beans to help meet your daily choline quota!
So, do plant-based eaters need to take supplements?
Not necessarily. The decision to take dietary supplements should always be discussed with your doctor (and based on your personal blood work), or with a Registered Dietitian who can assess your current diet and help you decide if/which supplements are right for you. If you live in the north (anyplace that has long and dark winters), a Vitamin D supplement (1000IU per day) is generally recommended as testing blood levels of this vitamin may not be part of routine blood work from your family doctor.
Some of my personal tips for optimizing your plant-based diet:
1. Plan ahead! Make a weekly meal plan to ensure you have the foods you need on hand to create nutritious, balanced meals. Planning your meals in advance also ensures you can prep time-consuming things (like soaking dried beans or sprouting grains) ahead of time. We also tend to waste less food when we plan because we can cook once and eat a few times, or roll leftovers into a new meal the next day.
2. Invest in time-saving appliances. A pressure cooker (like an instant pot) are huge time-savers for meals that require longer cook times like whole grains or pulses. A slow cooker is also a favorite of mine for making large batches of lentils or soups and stews.
3. Pack your own snacks. Make a batch of energy bites or protein bars or keep it simple with some fruit and nuts to avoid grabbing something quick and less-nutritious. If you know you’re heading out for more than a couple of hours, bring along a snack or two so you don’t wind up eating on the run!
Does your diet need to be 100% plant-based in order to be healthy?
Absolutely not! The bottom line is that a very healthy diet can include both plant foods and animal foods. We should however, put an emphasis on the majority of the food we eat in a day being of plant origin. For example instead of having an 8-ounce steak for dinner with 1/2 cup of cooked broccoli and 1 cup of mashed potatoes, have a 3 or 4 ounce steak instead, and fill up your plate with 2 cups of cooked broccoli, carrots, and cauliflower alongside your mashed potatoes. Or, you may choose to only eat meat once in awhile and that is perfectly fine too!
Some clients I’ve worked with over the years want to be 100% plant based. However, they sometimes struggle greatly with nutrient deficiencies (remember how much genetics can play a role in our absorption and metabolism of different nutrients?) Some of them have to take a handful of supplements every day in order to avoid these deficiencies. For them, including some animal products may be easier and more realistic rather than needing so much supplementation.
Try to not get too stressed out about labelling your diet, and just eat what feels right for you and keeps your body nourished and healthy. Being flexible with dietary choices is key to nutrition optimization!