By Lilli Link, MD on June 10, 2010

Iron In Your Diet

When it comes to getting iron from your diet, think Goldilocks. You don’t want too much and you don’t want too little. Fortunately, getting just the right amount is not that hard, even for people who don’t eat animal foods.

The main reason we need to be sure our bodies have adequate amounts of iron is to avoid anemia. This is a condition of too few red blood cells. Some of the first symptoms of this are fatigue, shortness of breath, rapid heart beat, and dizziness.

To understand why vegans (and their meat-eating friends and family who worry about them) might think they aren’t getting enough iron, it helps to know how iron in plant foods differs from iron in animal foods. Nonheme iron comes from both plant food and animal food. Heme iron is found only in the red blood cells and muscle cells of animal food. Both forms of iron have the same effect on the body, but heme iron is often thought of as the better source of iron because it is absorbed into the body more efficiently than nonheme iron. That means that even if a vegetarian meal has the same amount of iron as a piece of steak, the person eating the steak will absorb more iron than the person eating the vegetarian meal. In addition, meat, fish, and poultry help absorb the nonheme iron from vegetarian foods. But before you determine that nonheme iron is an inferior source of iron, read on.

While the absorption of heme iron is not affected much by other nutrients in the meal, nonheme iron is. So whether you are getting enough iron is not just about the amount of iron you eat, but which other foods you eat with it.

The following foods and nutrients inhibit nonheme iron absorption:
· Phytates, high in whole grains, legumes, nuts, and seeds.
· Polyphenols, high in coffee, tea, red wine, and fruit.
· Soy.
· Eggs.
· Foods high in calcium and calcium supplements.
· Milk protein. (If any of you Crazy Sexy readers are still eating dairy after reading my previous blog post about it, this is one more reason to stop!)

I know! I know! It seems like everything interferes with iron absorption and you might have to admit that your meat-eating friends are right. But don’t succumb just yet because there are plenty of vegan foods and food preparation techniques, listed below, that will increase nonheme iron absorption:
· Eating foods high in ascorbic acid (aka, vitamin C), such as fruits and vegetables, with your meal not only increases absorption, it also diminishes the negative effects of the inhibitors, listed above.
· Soaking and sprouting seeds, beans, and grains reduce the phytates.
· Leavening bread reduces phytates.
· Fermenting food reduces phytates.

But here is the best news about having only nonheme iron in your diet: Our bodies are unlikely to ever get overloaded with iron because the body absorbs more nonheme iron when our iron stores are low and less when our stores are high. (Of note, for the rare person with hemachromatosis, a severe overload of iron, this is probably not an effective way to keep iron stores low.) Heme iron, on the other hand, is absorbed regardless of your body’s iron stores, so you can end up having too much iron in your body.

If you explain all this to your friends and they are still worried about you, reassure them that studies show that although vegetarians generally store less iron in their bodies than meat eaters, the incidence of iron-deficiency anemia is about the same in both groups.

Although being low in iron might seem like a disadvantage, it may turn out that it is healthier for you. Iron is a pro-oxidant, meaning it activates free radicals which can damage DNA and make LDL (bad cholesterol) more damaging to the arteries. That is why some researchers are concerned that high iron levels could increase the risk for heart disease and some cancers. Since we don’t have a special mechanism in our bodies to get rid of iron, it makes sense to avoid taking in too much.

Given all these inhibitors and enhancers of nonheme iron absorption, it’s hard to know exactly how much a person needs in a day. Nevertheless, the Institute of Medicine recommends the following:

For omnivores:
Adult males: 8 mg/day
Adult females who are menstruating (not pregnant): 18 mg/day
Adult females who are post-menopausal: 8 mg/day

For vegetarians and vegans the recommended daily allowance is 1.8 times greater:
Adult males: 14 mg/day
Adult females who are menstruating (not pregnant): 32 mg/day
Adult females who are post-menopausal: 14 mg/day

(Please note that the needs for children vary as they grow.)

Vegan foods generally high in non-heme iron are dark green vegetables, dried fruit, seeds, nuts, and some grains. Here are some examples, along with the iron content of ground beef for comparison.

Food (100 gm; 3.5 oz): Iron content
Spirulina, dried: 28.5 mg
Cashews, raw: 6.7 mg
Sesame seed paste (aka tahini paste): 6.4 mg
Sunflower seeds, raw: 5.3 mg
Almonds, raw: 3.7 mg
Lentil sprouts, raw: 3.2 mg
Dandelion greens, raw: 3.1 mg
Kidney beans, red, cooked: 2.9 mg
Kelp, raw: 2.9 mg
Ground beef, cooked*: 2.8 mg
Spinach, raw: 2.7 mg
Figs, dried: 2.0 mg
Quinoa, cooked: 1.5 mg

*About 50% of the iron is in the form of heme iron which is the more easily absorbed form of iron.

Hopefully I’ve reassured you that, with a little forethought, you can get sufficient iron on a vegan diet. It is also possible on a vegetarian diet, though a bit more difficult because eggs and dairy interfere with iron absorption. However, there are certain situations in which it might be more challenging to get sufficient iron from food alone. In addition to the extra iron that menstruating women need, there are others who may not be able to get enough iron with diet alone:
· Pregnant women;
· People on dialysis;
· People with gastrointestinal disorders that affect iron absorption;
· People who engage in regular, intense exercise.

Anyone concerned that they aren’t getting enough (or are getting too much) iron should see their doctor about getting a simple blood test to check for anemia and to check their iron level.

Please note that if you are anemic and iron-deficient, your doctor may check your stool and urine for blood (even if you can’t see any blood). If all is well and you simply aren’t able to absorb enough iron from your diet to maintain a normal red blood cell count, talk to your doctor about whether you should take a low-dose iron supplement. And don’t forget to drink it down with fresh fruit or vegetable juice, which contains ascorbic acid, to help absorb it.

So the next time someone asks, “Don’t you need to eat meat for the iron?,” tell them that meat is not only unnecessary, but with its abundance of iron, may actually be a wolf in sheep’s clothing. And that’s no fairy tale!

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By Lilli Link, MD on April 8, 2009

Shedding Some Light On Dairy

The second most frequent question I hear when I tell someone I eat a primarily raw vegan diet or suggest one of my patients try it is, “Don’t you need milk for your bones?” If you don’t want to read all the way through the blog to get the answer, I’ll give it away right now: No!

Why would someone choose to stay away from dairy when ice cream and cheese taste so good and it’s supposed to be healthy? Even the government says we should be eating it. One reason to avoid dairy is based purely on logic, not science. It makes no evolutionary sense. No other mammal drinks milk after infancy, and certainly not the milk of a different species. In addition, although most people of European descent have adapted over the years so that they don’t lose the enzyme (lactase) necessary to digest dairy, more than half of the world’s population is lactose intolerant and can’t digest it.

But if those reasons aren’t convincing enough, here is a list of problems that have been shown in scientific studies to be associated with eating dairy: constipation, acne, asthma, and eczema. With regard to cancer, the evidence indicates dairy may be linked to a decreased risk of some cancers and increased risk of others. But it definitely increases a hormone called IGF-1 (insulin-like growth factor-1) which is a tumor promoter – something we cancer survivors would just as soon avoid. Finally, it is full of antibiotics, dioxin and hormones. Even if you are drinking organic milk from a cow who was never injected with bovine growth hormone, the milk is still full of the hormones she produced naturally.

So there are a lot of reasons to stay away from dairy. But doesn’t it help make your bones stronger? How else can you get enough calcium in your diet? The US RDA for calcium is 1000-1300mg/day, depending on your age and gender. In fact, it is hard to consume that much calcium if you are not eating dairy. This may be where the confusion begins. In a study that compared calcium consumption in different countries, the countries with the lowest calcium intake, about 500-1000mg/day, had lower rates of hip fractures (the dreaded outcome of low bone density) than the countries with the highest calcium intake (over 1000mg/day). Another study showed that countries with the highest consumption of animal protein intake had the most hip fractures, whereas the countries with the highest vegetable protein intake had the fewest hip fractures.

Although a number of studies show that eating dairy is associated with a decreased risk for fractures, a similar number of studies show it makes no difference. One of the major obstacles to getting a true picture of the importance of dairy for bone strength is the way the studies are done. Study participants are asked what they usually eat and then followed to see how many end up with broken bones. Since milk is touted as a healthy food, the people who eat the best and exercise the most are also the ones likely to be eating the most dairy. Curiously, of the scientific review articles about dairy and osteoporosis, most of the ones that showed a favorable association between dairy and bone health were sponsored by the National Dairy Council.

Since people from other countries who eat much less calcium than we eat have fewer fractures, maybe it’s not all about how much calcium we eat. Actually, more important is how much we keep. There are two other nutrients, in particular, which affect how much calcium we hold onto: protein and sodium. The more protein and sodium we eat, the more calcium we urinate out. So if we eat less protein and sodium (which are all too commonly consumed in a Western diet), we probably don’t need to eat as much calcium.

The other side of the equation is the absorption of calcium. It is better absorbed in an acidic environment, such as with vitamin C. That means that the lemon juice on your green leafy vegetable is helping you absorb the vegetable’s calcium. And vitamin D also increases the amount of calcium absorbed by the body.

Finally, it is becoming increasingly clear that there are other nutrients that are also very important for bone formation, such as vitamin K (high in dark green vegetables) and magnesium (high in green vegetables and seeds).

If you are wondering if a raw vegan diet can be okay for your bones, there has actually been a small study which suggests that it is. In this study, the people following the raw vegan diet were much thinner and had lower bone density (which goes along with being thinner). The reassuring part of the study was that the blood markers of bone turnover (i.e., how much bone was formed and broken down) showed no difference between those who followed the raw vegan diet and those who followed a typical American diet that contained almost twice the amount of calcium as the raw vegan diet.

Perhaps you are starting to think you might like to take dairy out of your diet, and you want to be sure you are still getting enough calcium. Good sources are dark green vegetables, nuts and seeds. Especially good foods are collard greens, kale, almonds and sunflower seeds.

Now if you are interested, theoretically, in cutting dairy out from your diet, but need some added incentive, read on. (If you still want to enjoy your milk, however, I suggest you stop reading now!) As a result of the milking process, cows often have mastitis (an infection of the udder), making dairy full of white blood cells, aka, pus. This means your yogurt, cottage cheese, ice cream, etc., are also full of pus.

It’s been 10 years since I have had dairy of any kind, and at this point I no longer even miss the cheese that sits on top of my former favorite food: pizza. But if you think you need some milk or cheese substitutes there are plenty of vegan (e.g., soy or rice-based) and raw (e.g., nut or seed-based) options to satisfy your palate!

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