Supplements And Plant-Based Diets: Do You Need Them?

A plant-based diet can be a healthy choice, but it's important to ensure you're getting all the nutrients your body needs. While you can get most of your essential nutrients from eating a variety of fruits, vegetables, whole grains, legumes, nuts, and seeds, there are a few key areas where you may need to consider taking supplements. Vitamin B12, for example, is found naturally in animal products, so those following a vegan or vegetarian diet may need to supplement this nutrient to avoid deficiency. Similarly, omega-3 fatty acids, particularly those found in fish and seafood, are important for heart and brain health, and while you can get plant-based omega-3s, their benefits may not be as pronounced. Vitamin D is another nutrient that may be lacking in a plant-based diet, especially if you're not getting regular sun exposure, and calcium, usually obtained from dairy products, can also be a concern. Iron is also more difficult to absorb from plant-based sources, so you may need to pair iron-rich foods with vitamin C to enhance absorption. Before taking any supplements, it's always a good idea to consult a healthcare professional to determine your specific needs.

Iron

Individuals following a plant-based diet are recommended to consume 1.8 times more iron than those who consume heme iron sources. This is because plant-based foods only contain non-heme iron, which has lower absorption rates. The recommended iron intake for adults varies depending on age and sex. Men aged 19 and above should aim for 8 mg daily, while women aged 19-50 should aim for 18 mg. Pregnant women aged 19-50 should aim for 27 mg daily, and breastfeeding women in the same age group should aim for 9 mg. It's important to note that these recommendations are for individuals on a plant-based diet, and those consuming heme iron may have different requirements.

Meeting iron needs through dietary sources is generally recommended over supplementation. Plant-based sources of iron include legumes (beans, peas, and lentils), dark green vegetables, wholegrain or fortified products, nuts, and seeds. Here are some specific examples of plant-based foods that can contribute to daily iron needs:

• Lentils, cooked (3/4 cup) - 4-6 mg iron per serving
• Oatmeal, cooked (3/4 cup) - 4-6 mg iron per serving
• Bulgar, cooked (1 cup) - 4-6 mg iron per serving
• Blackstrap molasses (1 tablespoon) - 2-4 mg iron per serving
• Pumpkin seeds, roasted (1/4 cup) - 2-4 mg iron per serving
• Spinach, cooked (1/2 cup) - 2-4 mg iron per serving
• Tomato puree (1/2 cup) - 2-4 mg iron per serving
• Beans (most varieties), cooked (3/4 cup) - 2-4 mg iron per serving
• Edamame, cooked (3/4 cup) - 2-4 mg iron per serving
• Peas, cooked (3/4 cup) - 2-4 mg iron per serving
• Soy-based yogurt (3/4 cup) - 2-4 mg iron per serving
• Tempeh/fermented soy product (3/4 cup) - 2-4 mg iron per serving
• Tofu, cooked (3/4 cup) - 2-4 mg iron per serving
• Asparagus, raw (6 medium spears) - 1-2 mg iron per serving
• Apricots, dried (1/4-1/2 cup) - 1-2 mg iron per serving
• Kale, cooked (1/2 cup) - 1-2 mg iron per serving
• Beets, cooked (3/4 cup) - 1-2 mg iron per serving

It's important to note that certain dietary factors can impact iron absorption. Phytates and polyphenols, found in many plant-based foods that contain iron, can bind to non-heme iron and interfere with absorption. Soaking grains, nuts, and seeds prior to cooking can help reduce phytate or polyphenol content and increase iron absorption. Additionally, tannins found in black tea, espresso, coffee, and red wine can decrease non-heme iron absorption when consumed with meals. It is recommended to consume these beverages 30 minutes before or after a meal to limit their interference with iron absorption.

On the other hand, vitamin C is known to increase the body's ability to absorb iron. It is often recommended to pair iron-rich foods with vitamin C-rich sources, such as citrus fruits, kiwis, strawberries, sweet bell peppers, potatoes, and broccoli. For example:

• Having berries with oatmeal
• Adding spinach and oranges in smoothies
• Enjoying tofu with bell peppers in a stir fry
• Using tomato as a base for bean, pea, or lentil-containing dishes
• Garnishing with freshly squeezed lemon

In summary, it is possible to meet iron requirements on a plant-based diet by making balanced food choices and incorporating iron-rich plant-based foods with vitamin C-rich foods. However, it is important to be mindful of factors that can interfere with iron absorption, such as tannins and polyphenols, and separate the consumption of tea and coffee from iron-rich meals.

Calcium

While it is possible to obtain all of the calcium your body needs solely from food, those on a plant-based diet may need to be more mindful of their calcium intake, as vegans have been found to have lower calcium intake than vegetarians and omnivores. This is because non-vegans get most of their calcium from dairy foods such as milk, cheese, and yoghurt.

Good plant-based sources of calcium include:

• Green, leafy vegetables such as broccoli, cabbage, and bok choy
• Fortified unsweetened soya, pea, and oat drinks
• Sesame seeds and tahini
• Bread (in the UK, calcium is added to white and brown flour by law)
• Dried fruit, such as raisins, prunes, figs, and dried apricots
• Beans, lentils, nuts, seeds, and soy foods including tofu, although these are only consumed in smaller amounts that add up

Some foods are better sources of calcium than others because high levels of oxalate, a natural substance in food that binds to calcium during digestion, can interfere with absorption. Foods with high oxalate levels include spinach, beet greens, and Swiss chard.

It is recommended to obtain calcium from food sources over supplements where possible, as food sources provide added benefits such as energy, fibre, vitamins, minerals, and antioxidants. However, if it is not possible to obtain the recommended amount of calcium from food, then supplements may be taken.

When taking calcium supplements, it is important to note that more is not always better. It is very important to calculate your average daily calcium intake from food and only supplement with the difference. It is also recommended to avoid taking more than 500 mg in one dose, as our bodies cannot absorb calcium as efficiently in larger doses.

Iodine

Vegans are considered at risk of iodine deficiency, with studies reporting that they have up to 50% lower blood iodine levels than vegetarians. To ensure adequate iodine intake, vegans who do not consume iodized salt or eat seaweed regularly should consider taking an iodine supplement containing potassium iodide. It is important to choose supplements containing potassium iodide over kelp, as kelp may contain small amounts of arsenic. Additionally, kelp-based supplements may vary widely in their iodine content.

Some iodine supplements available on the market include Genestra Brands Liquid Iodine, Best Naturals Kelp Supplement, Nascent Iodine Premium Formula Supplement Drops, and Detoxadine Certified Organic Premium Nascent Iodine Supplement. It is important to note that while iodine is crucial, excessive intake can also lead to health issues. Therefore, it is recommended to stay within the suggested daily intake levels.

Vitamin B12

For vegetarians, good sources of vitamin B12 include:

• Yogurt
• Low-fat milk
• Swiss cheese
• Eggs
• Fortified cereals
• Nutritional yeast

For vegans, vitamin B12 can be obtained from:

• Fortified foods such as plant-based milk, breakfast cereals, and nutritional yeast
• Seaweed
• Shiitake mushrooms

It is important to note that while some plant foods like seaweed, algae, and certain mushrooms contain small amounts of vitamin B12, more research is needed to determine the amounts and bioavailability of this nutrient in these sources.

The recommended daily allowance (RDA) of vitamin B12 varies depending on age and life stage:

• Adults and teenagers: 2.4 micrograms (mcg) per day
• Children between 9 and 13 years old: 1.8 mcg per day
• Children between 4 and 8 years old: 1.2 mcg per day
• Toddlers between 1 and 3 years old: 0.9 mcg per day
• Infants between 7 and 12 months old: 0.5 mcg per day
• Babies below 6 months old: 0.4 mcg per day
• Pregnant women: 2.6 mcg per day
• Breastfeeding women: 2.8 mcg per day

Vitamin D

Fortified foods that contain vitamin D include soy milk, almond milk, rice milk, orange juice, fat spreads, breakfast cereals, and unsweetened soya drinks. Mushrooms are one of the only non-animal sources of vitamin D, and mushrooms exposed to ultraviolet light when growing may contain about 450 IU per 100-gram serving.

Sunshine is also a great source of vitamin D for vegans. Exposing your skin to sunlight can increase your body's natural vitamin D production. For most people, 10 to 30 minutes of sun exposure three times a week is sufficient. However, people with darker skin may need more sun exposure than those with lighter skin to get the same benefits.

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