The Lowdown On Omega-3s — How Important Are They For Plant-Based Eaters?
"Out of nowhere, I'm overcome with crippling fatigue."
That was the opening line from an email we received from Sarah, a 53-year-old woman from New Hampshire.
Sarah is active — she runs a few 10Ks and half marathons each year — and has been thriving on a whole food plant-based diet for the past four years.
But when she wrote us (while waiting on blood results from her doctor), she was desperate for answers.
As we later discovered, Sarah was deficient in iron, an essential metal for all living things.
Too little iron can cause issues from your brain to your nails (including the fatigue Sarah was experiencing), but too much can be equally as dangerous.
So let's get to the bottom of why iron is so important, how you can avoid Sarah's situation, and the best plant-based sources to support your long-term health.
What Iron Does (and Why it's Important for Your Health)
The role of iron is rather simple:
It forms hemoglobin, a vital protein found in red blood cells.
Hemoglobin's primary function is to carry oxygen from the lungs to the body's tissues and return carbon dioxide from the tissues back to the lungs.
(Interesting side note: Hemoglobin is also responsible for the vibrant red color of blood when it's exposed to oxygen.)
A deficiency in hemoglobin often leads to anemia, characterized by symptoms like fatigue, weakness, shortness of breath, and pale skin, as the body's tissues and organs don't receive enough oxygen.
On the flip side, maintaining adequate levels of iron presents a number of benefits, like
- Enhanced energy and vitality
- Improved focus and memory
- Stronger immunity
- Elevated mood and mental health
Simply put, you need iron to survive, and you need adequate iron to feel your best.
Heme vs. Non-heme Iron, Understanding the Difference
You may have heard the argument from meat eaters that plant-based sources of iron aren't adequate.
And while that's not true, there are differences between the two types of dietary iron:
Heme iron constitutes approximately 40% of the iron in meat, poultry, and fish.
Heme iron gets its name because it's bound to a heme group, a component of hemoglobin and myoglobin found in animal muscles. This binding allows it to be highly bioavailable (absorbed at a rate of approximately 15-35%).
While absorbed at a high rate, recent research has highlighted the potential dangers of heme iron. Excessive consumption of heme iron has been linked to certain health risks, including an increased risk of colorectal cancer.
Non-heme iron, on the other hand, is the form found in plant-based foods like legumes, grains, nuts, seeds, and vegetables.
It also accounts for the majority — about 60% — of the iron in animal tissue.
The argument against plant-based sources of iron comes from the fact that the absorption rate of non-heme iron is significantly lower, ranging from 2-20%.
Why such a big range?
The absorption rate is influenced by various dietary factors. For instance, certain components in food, like phytates found in grains and legumes, can inhibit non-heme iron absorption.
Should Vegans and Vegetarians Worry About Getting Enough Iron?
With such a low absorption rate of non-heme iron, does that mean plant-based eaters are routinely not getting enough?
As always, there's nuance.
The current Recommended Dietary Allowances (RDAs) of iron for omnivorous adults aged 19-50 are:
- 8 mg for men
- 18 mg for women
- 27 mg for women during pregnancy
- 9 mg for women who are lactating
But for plant-based eaters, the RDAs are 1.8 times higher.
Now before you panic, that sounds a little scarier than it actually is.
Many plant foods (like leafy greens) are very rich in non-heme iron, and there are a few ways to increase the absorption rate, like consuming vitamin C alongside iron-rich plant foods.
So how much iron should vegetarians, vegans, and plant-based eaters strive for?
Following the recommended 1.8x the standard RDA for people aged 19-50, it would be:
- 14.4 mg for men
- 32.4 mg for women
- 48.6 mg for women during pregnancy (Important note, this is approaching the upper limit of tolerable intake. Always consult your healthcare professional before supplementing with iron.)
- 16.2 mg for women who are lactating
While that may sound like a lot on paper, hitting these benchmarks through a whole food plant-based diet isn't incredibly difficult.
How do your iron needs change after the age of 50?
Remember Sarah who wrote the email that triggered this post?
Being over 50, her RDA for iron is actually less than those listed above.
For both 50+ men and women omnivorous, the RDA is 8mg, which means plant-based eaters should get at least 14.4 mg per day.
But studies show that as you age, your iron metabolism changes. The result is higher rates of anemia, especially in the elderly. (This was likely Sarah's problem, even at 53).
In the United States, studies suggest that around 11% of men and 10% of women aged 65 and older experience anemia, approximately doubling by the age of 85.
Moreover, in residential and nursing home settings, the incidence of anemia is even higher, with rates reaching between 50% and 60%.
How to Increase Iron Absorption from Plant-Based Foods
I mentioned earlier there are a few techniques to increase your absorption of iron.
Here are the best research-backed options:
Incorporate Vitamin C-Rich Foods: Eating foods high in Vitamin C alongside non-heme iron sources can boost iron absorption. This is due to Vitamin C's ability to convert non-heme iron into a form that's more easily absorbed by the body.
Sprout or Fermented Your Grains and Legumes: Sprouting or fermenting your grains can reduce the levels of phytates, natural compounds known to impede iron absorption.
Limit Coffee and Tea During Meals: An analysis of over 27,000 Koreans found that consuming coffee and tea with meals can inhibit iron absorption.
Should You Supplement a Plant-Based Diet With Iron?
Supplements play an important role in helping some vegetarians, vegans, and plant-based eaters get adequate amounts of iron.
But because iron has an upper limit of tolerable intake, a blanket statement that all plant-based eaters should supplement with iron is irresponsible.
Men, women, various age groups… we all have different needs, and getting too much iron can be just as dangerous as getting too little.
In fact, this is why we don’t include iron in Complement Essential, inspite of the fact that many people could benefit from it.
To best understand whether you should take an iron supplement, we recommend to take a blood test and consult your healthcare provider.
Increasing your iron intake through real foods is a great way to reduce your risk of anemia without a dedicated supplement.
Iron-Rich Plant-Based Foods
Lentils: 6.6 mg per cup (cooked)
Chickpeas: 4.7 mg per cup (cooked)
Tofu: 6.8 mg per cup (raw, extra firm)
Black-eyed peas: 4.3 mg per cup (cooked)
Nut and Seeds:
Pumpkin: 2.5 mg per ounce
Sesame: 1.31 mg per tablespoon
Cashews: 1.9 mg per ounce
Almonds: 1.1 mg per ounce
Flaxseed: 1.6 mg per ounce
Broccoli: 1 mg per cup (cooked)
Brussels Sprouts: 1.8 mg per cup (cooked)
Sweet potatoes: 2.2 mg per large potato (peeled)
White mushrooms: 2.7 mg per cup (cooked)
Spinach: 6.4 mg per cup (cooked)
Kale: 1.2 mg per cup (raw)
Swiss Chard: 3.9 mg per cup (cooked)
Beet greens 2.7 mg per cup (cooked)
Quinoa: 2.8 mg per cup (cooked)
Spelt: 3.7 mg per 100 g (flour)
Oats: 1.2 mg per cup (cooked)
Note: Nutrient amounts may vary depending on the source.
5 Plant-Based Recipes Rich in Iron
Sarah Reversed Her Anemia — You Can Avoid It Altogether
What should you make of all this?
No question that maintaining proper levels of iron is essential to living a healthy, vibrant life.
And with proper care and attention, plant-based eaters should have no more trouble hitting RDAs than anyone else.
Ensure you're getting the recommended amount — either through whole foods or an iron supplement — and get your blood tested periodically to catch any changes in your body's ability to absorb iron.
50% of Your RDA of Iron in a Single Glass
Want a simple, flexible way to help ensure you're getting the essential nutrients your body needs to thrive?
Recent testing showed that Daily Greens contains up to 50% of your RDA of iron per serving.
The delicious, non-grassy taste of Daily Greens places plant-based iron and superfood greens on autopilot.