Rows of different colored dry beans. Red kidney beans, brown pinto beans, white cannellini beans, green lentils.

Protein, Hormones, Zinc, and Digestive issues

Today we’ll conclude our 4-part series on potential complications from eating a plant based diet. While negative side effects are rare, they can happen. This article will discuss the role of protein, zinc, and hormones in our bodies and how they are affected by a plant based diet. We’ll also address potential digestive and intestinal complications and how to prevent them.

In general, a plant based diet is considered safe and one of the best diet options for overall health. Those eating a balanced, mostly whole food plant based diet rarely suffer negative reactions. 

By eating a balanced diet with a wide variety of different fruits, vegetables, beans, and grains, you can almost be certain a vegan diet will be beneficial to your health and wellbeing.

In fact, The Academy of Nutrition and Dietetics stated in 2016:

“Vegan diets are healthful, nutritionally adequate, and may provide health benefits for the prevention and treatment of certain diseases. These diets are appropriate for all stages of the life cycle, including pregnancy, lactation, infancy, childhood, adolescence, older adulthood, and for athletes. Plant-based diets are more environmentally sustainable than diets rich in animal products because they use fewer natural resources and are associated with much less environmental damage.”

That being said, it’s extremely important that you discuss all dietary changes with your physician and consult with a registered dietician.

Wide variety of colorful dried beans at a market. Beans are a great source of vegan protein.

What is protein?

Protein is a macronutrient, essential for energy and building muscle. Proteins are made up of amino acids. A well-balanced plant based diet will provide adequate amounts of essential amino acids and prevent protein deficiency.

In general, most patients on a plant based diet are not at risk for protein deficiency. Studies have shown that most vegans are not protein deficient; however, the fact that some vegans have a high intake of processed foods means they may not be getting an adequate amount of fruits, vegetables, and whole grains.

Plant based Asian noodle bowls with tofu and mixed vegetables: a good source of vegan protein.

Protein intake and the plant based diet

Similar to the lies by the dairy industry that we must drink milk to have strong bones and prevent osteoporosis, another common falsehood is that we need meat to get enough protein. (Remember, the meat and dairy industries use the exact same marketing and promotion tactics as the tobacco industry once used…)

On the contrary, plant based protein sources are abundant and protein deficiency is rare. In fact, most Americans are getting twice the amount of protein in their diet than they actually need.

High protein diets can lead to an increased risk for kidney stones, kidney disease, and osteoporosis. Additionally, saturated fat intake from red meat increases risk of heart disease and colon cancer. High protein diets from plant sources do not carry these same risks.

In defense of this fact, the animal-based food industry sponsored a summit to discuss the “misperceptions that Americans over-consume protein.”

Surprising to most people is that nearly all vegetables, beans, grains, nuts, and seeds contain some (and often a lot of) protein. 

Soybeans and quinoa are complete proteins, meaning they contain all 9 essential amino acids. Other plant foods only contain some of the essential amino acids, so a balanced, varied diet is crucial.

Recommended daily intake for the average (non-athlete) person is 0.36 g protein per pound of body weight.

Vegan dinner bowl of tofu, edamame, and other fresh vegetables: a good source of vegan protein.

Plant based protein sources

  • Soybeans (1 cup cooked = 31 g)
  • Edamame (½ cup = 10 g)
  • Soy products
    • Tofu (1 cup = 34 g)
    • Tempeh (½ cup = 15 g)
    • Seitan (3 oz = 21 g)
    • TVP (½ cup = 12 g)
  • Beans & Legumes
    • Lentils (1 cup cooked = 18 g)
    • Black, kidney, chickpeas, pinto, and lima beans (1 cup cooked = 15 g)
    • Peanuts (½ cup = 20 g)
    • Peas (1 cup cooked = 9 g)
  • Quinoa (1 cup cooked = 8 g)
  • Wild rice (1 cup cooked = 7 g)
  • Oats (½ cup dried = 6 g)
  • Peanut butter (2 tablespoons = 8 g)
  • Almonds (¼ cup = 8 g)
  • Cashews (¼ cup = 5 g)
  • Nutritional yeast (¼ cup = 8 g)
  • Potato (large baked potato = 8 g)
  • Mushrooms (5 medium mushrooms = 3 g)
  • Spinach (1 cup cooked = 5 g)
  • Broccoli (1 cup cooked = 4 g)
  • Brussel sprouts (1 cup = 3 g)
  • Asparagus (1 cup = 3 g)
  • Kale (1 cup = 2 g)
  • Blackberries (1 cup = 2 g)
  • Banana (1 large banana = 2 g)
  • Hemp seeds (1 tablespoon = 5 g)
  • Chia seeds (1 tablespoon = 2 g)
Variety of different dried beans which are a good vegan source of protein.

What is zinc?

Zinc is a mineral that plays an important role in regulating the immune system (and reducing incidences of the common cold), metabolism, and repair of damaged DNA.

Found in limited amounts in plant based foods (and absorbed less from plant foods), zinc deficiency can occur. A deficiency in zinc can lead to impaired immune system, slow wound healing, hair loss, and loss of appetite.

Phytates, which are commonly found in plant foods, reduce zinc absorption. Some researchers have suggested that this increases the zinc needs of vegetarians by up to 50%. On the other hand, a 2013 study showed vegans had only a slightly lower zinc level in their blood than meat eaters.

Protein increases zinc absorption. Foods such as legumes and nuts are high in both protein and zinc and are therefore great choices to obtain both in the diet.

Oatmeal topped with fresh fruit.

Zinc and the plant based diet

Recommended daily intake of zinc:

  • Men: 11 mg
  • Women: 8 mg

Plant based zinc sources:

  • Oatmeal (1 cup cooked = 2.3 mg)
  • Fortified cereals
  • Quinoa (1 cup = 2 mg)
  • Tofu (½ cup firm tofu = 2 mg)
  • Cashews (¼ cup dry roasted = 2 mg)
  • Lentils (1 cup = 3 mg)
  • Black beans (1 cup cooked = 2 mg)
  • Garbanzo beans (½ cup = 1.3 mg)
  • Wild rice (1 cup = 2 mg)
  • Peanuts, Almonds, and Pecans (¼ cup = 1.1 mg)
  • Tempeh (½ cup = 1 mg)
  • Hemp seeds (2 tablespoons = 3 mg)
  • Pumpkin seeds (2 tablespoons = 2 mg)
  • Chia seeds (2 tablespoons = 1 mg)
  • Peanut butter (2 tablespoons = 1 mg)
  • Green peas (1 cup cooked = 2 mg)
  • Spinach (1 cup cooked = 1 mg)
  • Broccoli (1 cup cooked = 0.8 mg)
  • Shiitake mushrooms (1 cup cooked = 2 mg)
  • Avocado (1 whole = 1 mg)
3-D color model of the human brain.

Hormones

Hormones have profound effects on mental, physical, and emotional health. They are chemical messengers that play a major role in appetite control, weight, mood, and a variety of other things. It is the job of the endocrine gland to produce the precise amount of hormone needed for each function. However, because of diet and lifestyle, many people experience hormone imbalances. Additionally, some hormones decline with age.

The hormones especially affected by diet include estrogen, insulin, glucagon, and cortisol.

Woman doing upward facing dog pose on yoga mat.

Natural Ways to Balance Hormones

  1. Eat enough protein: helps with feeling full and weight control
  2. Consume a high fiber diet: stimulates production of hormones that make you feel full and satisfied
  3. Regular exercise
  4. Avoid or minimize sugar intake (including sugary beverages)
  5. Avoid or minimize refined carbohydrate intake (such as white bread and white pasta)
  6. Learn to manage stress: cortisol and adrenaline are greatly affected by stress
  7. Consume healthy fats: may help with appetite control and reduce insulin resistance
  8. Avoid overeating or undereating: creates hormonal shifts that can lead to weight problems
  9. Consume enough omega-3 fatty acids
  10. Get enough sleep
Soybeans next to a glass of soy milk.

Soy and Estrogen

Estrogen is the primary female sex hormone (but it is present in males as well). Estrogen levels fluctuate dramatically throughout a woman’s cycle, and levels drop significantly when a woman hits menopause.

Only produced in the body, estrogen cannot be obtained from the diet; however, various plant foods contain phytoestrogens. These are chemicals that weakly act like estrogen in the body, and may help relieve some symptoms of menopause. Phytoestrogens are not human hormones, though.

Plant phytoestrogens, especially in soybeans and legumes, are converted by bacteria in the intestines to hormone-like compounds with estrogen-like (and anti-estrogen like) activities. Again, they are not actual human hormones.

Soy is the richest food source of phytoestrogens. Hundreds of studies have been conducted on a diet rich in soy and the effects on human hormones, and there are plenty of conflicting results. Most scientists agree, however, that because soy does not actually contain estrogen, it has more positive than negative effects on the human body. Furthermore, phytoestrogens are actually antioxidants.

Worth noting, the same cannot be said for dairy. Cow, goat, or any type of mammal milk does contain human hormones, including estrogen. And there are plenty of study results that show a link between dairy consumption and increased health risks, including cancer and heart disease. In fact, most research indicates soy consumption actually slows or prevents cancer growth.

Side note: soybeans are the number one genetically modified crop in the world. To avoid GMOs, always buy organic soy products.

Yellow, orange, red, purple, and green fresh squeezed juices.

Digestive issues

Many people associate a vegan diet with digestive and intestinal issues, when, in fact, the opposite is true. The traditional Western diet is actually the one responsible for rapidly increasing levels of serious digestive issues over the past 5 decades.

The gut is constantly changing and adapting, responding to the foods we eat. Rich in fiber, vitamins, minerals, and water (and lacking hard to digest products such as red meat, dairy, and eggs), a plant based diet is gut-healthy and enhances your digestive system. However, some people do experience digestive difficulties.

A common mistake people make when switching to a plant based diet is they substitute meat and dairy with store bought vegan alternatives. While these products may help you transition to the new way of eating, processed foods can be hard on your intestines and be difficult to digest. Stick to a whole food plant based diet as much as you can and avoid processed foods.

When including more beans and grains in your diet, soak dry beans and grains overnight, rinse them, and then cook well. This process can help aid in digestion and reduce bloating. Also, eat more leafy greens, which help heal the digestive system and reduce inflammation.

Keep in mind that when you consistently eat meat and dairy, your body has grown accustomed to the chronic inflammation associated with this way of eating. It may take a little bit of time for your body to heal and adjust to the new diet. But once it does, it’s so worth it! 🌱

In fact, a whole food plant based diet produces the best outcomes when it comes to managing and avoiding conditions such as Inflammatory Bowel Disease, Irritable Bowel Syndrome, fatty liver disease, and bowel cancer.

Fresh ginger tea.

Leaky Gut

Intestinal Permeability (IP), also known as Leaky Gut Syndrome, is a condition that creates gaps in the lining of the intestinal wall. Food particles, bacteria, and waste products escape through these gaps and deposit directly into the bloodstream.

Not a lot is known about IP, but there is growing evidence that the standard American diet (low in fiber and high in sugar and saturated fats) may initiate this process. There is also a link to heavy alcohol use and stress.

A poor ratio of good and bad gut bacteria can cause increased inflammation and risk for leaky gut. Eat a well balanced diet with plenty of fruits, vegetables, whole grains, and probiotic and prebiotic-rich foods (see below).

Kirkland brand organic Kombucha, a probiotic source.

How to prevent intestinal issues

The best plant based foods for digestion include foods that are rich in fiber, contain probiotics and prebiotics (which stimulate growth of healthy gut bacteria), and foods that contain naturally occurring digestive enzymes. (When increasing fiber intake, it’s also important to increase and monitor water intake as well to aid in digestion.) 

For the average person, the recommended daily intake of fiber is 25 g for females and 38 g for males.

Probiotics are live bacteria that help replenish beneficial flora essential to our immune system. Prebiotics are types of fiber that good bacteria in the gut feed on. Good bacteria in the digestive tract protects us from harmful bacteria and fungi. In addition to assisting the immune system, they also help regulate inflammation.

Studies have shown plant based diets may be effective in promoting gut health, beneficial gut microbes, and overall health.

High fiber foods

  • Chia seeds
  • Oats
  • Lentils
  • Apples (especially the peel, so don’t discard it)
  • Bananas
  • Blueberries, raspberries, blackberries
  • Sweet potatoes
  • Avocados
Glass container of spicy vegan kimchi.

Probiotic-rich fermented foods

  • Plant based yogurts (made with coconut, cashew, almond milk, etc)
  • Kombucha
  • Tempeh
  • Sauerkraut
  • Kimchi 

Prebiotic-rich foods

  • Garlic
  • Onion
  • Leeks

Digestive-aid foods and foods with naturally occurring digestive enzymes

  • Fennel
  • Ginger (also calms nausea and other stomach discomfort)
  • Peppermint (can also calm nausea and sooth stomach and intestines)
  • Cayenne
  • Cumin
  • Papaya
  • Pineapple
Fresh herbs, spices, garlic, and ginger on a cutting board.

A plant based diet is a wonderful thing 🥰

Recognizing that each person is unique, it’s important to consult a registered dietician for your individual dietary needs.

Don’t let any of these potential complications deter you from trying a plant based diet! As I said before, most people experience no negative side effects whatsoever, and those that do, are usually able to resolve it by tweaking their vegan diet. The positive health outcomes far outweigh the rare complications associated with a plant based diet. 🌱

On average, vegans have:

  • 50-75% lower rates of high blood pressure
  • ⅔ lower risk of developing type 2 diabetes
  • 15-20% lower risk of cancer
  • Significantly lower cholesterol levels

As stated in the medical journal article titled, Nutritional Update for Physicians: Plant-Based Diets:

“Too often, physicians ignore the potential benefits of good nutrition and quickly prescribe medications instead of giving patients a chance to correct their disease through healthy eating and active living. If we are to slow down the obesity epidemic and reduce the complications of chronic disease, we must consider changing our culture’s mind-set from ‘live to eat’ to ‘eat to live.’ The future of health care will involve an evolution toward a paradigm where the prevention and treatment of disease is centered, not on a pill or surgical procedure, but on another serving of fruits and vegetables.”

What has surprised you most about a plant based diet? Subscribe to the blog for continued plant based diet information, recipes, and insight into my journey of veganism. 🥰

White onions, green bell pepper, garlic, and bright red tomatoes with a bunch of cilantro on a wooden cutting board. Also pictured are bowls of variety of ground spices.

2 thoughts on “Protein, Hormones, Zinc, and Digestive issues”

  1. INTERESTING! Took 8 screen grabs of your info! The older I get the more I see change in eating, appetite, body shape-UGH!!! Would hear the older ladies talking about this while working out and thought, “I find that hard to believe!” Now I’m living it!!! Thanks for all of the information and encouragement! God Bless!!

    1. We’ve all been there–“it’ll never happen to me”…and then next thing you know, it happens. 😫
      But then you have to step back and be thankful for health and all the blessings in life! ❤️

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