Iron & Anemia (and the Plant Based Diet)

While a plant based diet is generally considered safe and one of the healthiest diet options, there are some rare potential complications to be aware of. For the next 4 Tuesdays, I will be addressing these possible side effects and how to avoid them. Today, we’ll talk about low iron and anemia. 

Again, I cannot stress this enough: people eating a balanced plant based diet rarely suffer from negative reactions. Following a balanced, mostly whole food plant based diet almost guarantees positive health outcomes with no negative side effects and consumption of all essential nutrients.

That being said, every single person is different and what works for one person may not work for the next person. It’s important to discuss all diet choices with your physician and get regular blood work and routine checkups.

What is iron?

Iron is an essential mineral for blood production, present in every cell of the body. Most of the body’s iron is found in the red blood cells in a protein called hemoglobin. Hemoglobin has a critical role in transferring oxygen throughout the body.

Iron is not made in the body and must be absorbed from what we eat.

There are two types of dietary iron:

1. Heme iron: only found in animal foods and is absorbed well in the body
2. Non-heme iron: found in animal and plant foods; is more common but is not as easily absorbed by the body

Although it is more easily absorbed, heme iron is not essential to the human diet. Non-heme iron accounts for the majority of iron intake in the United States (85-90%).

When iron intake is consistently low, this can lead to iron deficiency anemia.

Iron Deficiency Anemia causes and symptoms

Low iron in the blood (iron deficiency) is globally one of the most common nutrient deficiencies. In fact, more than 25% of people in the world are affected by iron deficiency.

The most common result of iron deficiency is anemia: the number of red blood cells in the body decreases and the body’s ability to transfer oxygen declines. 

Those groups at increased risk for iron inadequacy include:

• Pregnant women
• Infants and young children
• Women with heavy menstrual bleeding
• Cancer patients
• People with gastrointestinal disorders (such as Crohn’s disease, celiac disease, and ulcerative colitis) 
• Heart failure patients

Iron deficiency anemia affects 1 in 4 people. Vegans may be at increased risk due to only consuming non-heme iron.

Common symptoms of iron deficiency anemia include tiredness, weakness, dizziness, shortness of breath, impaired brain function, pale skin, heart palpitations, and weakened immune system. 

Iron intake and the plant based diet

The best plant based sources of non-heme iron include beans, seeds, and dark leafy greens. For instance (depending on age and dietary requirements):

• ½ cup of cooked beans provides as much as 33% of the daily value of iron
• 1 ounce of roasted pumpkin seeds provides 11% of the daily value
• 1 ounce of fresh kale provides 5.5% of the daily value

It should be noted that plant based iron sources are healthier than animal based iron sources. For example, eating 1,700 calories of sirloin steak yields the same amount of iron intake as eating 100 calories of spinach.

The National Institute of Health recommends:

• 8 mg of iron per day for women over 50 years old and all adult males
• 18 mg of iron per day for women ages 19-50
• 27 mg of iron per day for pregnant women

Recommended daily iron intake for vegans and vegetarians may be as much as 1.8 times higher than these amounts. (This is debated among researchers and the medical community, so it’s important to discuss this with your doctor.)

Some of the best plant based iron sources include:

• Lentils (1 cup cooked = 6.6 mg of iron)
• Cannellini beans (1 cup cooked = 5.2 mg iron)
• Chickpeas (1 cup = 4.74 mg iron)
• Black-eyed peas (1 cup = 4.3 mg iron)
• Red kidney beans (1 cup = 5.2 mg iron)
• Spinach (1 cup = 6.4 mg iron)
• Swiss chard
• Kale
• Mushrooms
• Tofu (½ cup = 6.65 mg iron)
• Amaranth (1 cup cooked = 5.17 mg iron)
• Quinoa
• Oatmeal
• Fortified cereals
• other fortified foods
• Baked potatoes, especially with the skins on (1 medium potato = 2 mg iron)
• Hulled hemp seeds (3 tablespoons = 2.38 mg iron)

Other iron-rich foods include raisins, dried apricots, cashews, cabbage, and tomato juice. Even 3 ounces of dark chocolate contains 7 mg of iron!

Vitamin C and iron absorption

Vitamin C can help enhance the body’s absorption of iron. Eating vitamin C-rich foods while eating iron-rich foods can help maximize iron absorption (up to 6 times as much). Good sources of vitamin C include:

• Bell peppers
• Cantaloupe
• Cauliflower
• Citrus fruits
• Kiwi
• Mango
• Strawberries
• Sweet potatoes
• Tomatoes

Foods high in iron and vitamin C provide the best absorption. These include:

• Broccoli
• Bok choy
• Kale
• Spinach
• other dark leafy green vegetables
• Hummus with lemon juice

Foods reducing iron absorption should be avoided for 2 hours before and after iron-rich meals. These include:

• Black tea, peppermint tea, and coffee
• Calcium supplements
• Wine
• Antacid medications

Because too much iron can be harmful to your body, iron supplements should only be taken when prescribed by your doctor.

Plant Based Diet conclusions

To reiterate, research has shown time and again that people eating plant based diets generally require fewer medical interventions and medications and have lower risk of heart disease, high blood pressure, high cholesterol, diabetes, certain cancers, and obesity.

While red meat contains the highest source of iron, it’s also important to remember the downsides to eating red meat. Studies have shown that decreased consumption of red meat has been associated with lower mortality rates from cardiovascular-related causes and lower mortality rates in general.

Additionally, the American Dietetic Association states that iron deficiency anemia is rare, even in those individuals who follow a strict plant based diet.

I had routine blood work drawn about 6 months after starting a 100% plant based diet. I eat a wide variety of fruits, vegetables, grains, beans, and seeds, and I take a daily multivitamin. All of my numbers were within normal limits, and I personally have not experienced any negative side effects to eating a vegan diet.

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

Have you ever experienced negative side effects from any particular diet or way of eating? How did you combat this? Let me know in the comments below, and leave any additional questions you may have!