Heart disease is now the leading cause of death in industrialized countries, with less developed countries catching up fast. As we all know, this is largely due to obesity, overconsumption of salt and red meat, lack of exercise, and simply the fact that we generally lead inactive, unhealthy lives.
But could vitamin B12 provide a lifeline? Is it possible that B12 plays a role in preventing heart disease, or at least lowering the risk?
The evidence certainly seems to suggest so.
Homocysteine is a non-protein amino acid that we all have inside our bodies. We have to internally synthesize it ourselves, as we cannot get homocysteine from our diets. However, a high level of homocysteine in the body is a known independent risk factor for coronary artery disease, and has also been associated with an increased risk of clotting abnormalities, heart attacks and strokes (because of the blood clots).
What Does This Have To Do With vitamin B12?
Vitamin B12 is needed to effectively break down homocysteine and keep levels of the compound low. So without enough B12, homocysteine levels rise and suddenly you’re at a greater risk of heart disease.
On average, for every 5μmol/l above 10μmol/l of serum homocysteine, the patient has a 20% greater risk of suffering from circulatory health problems. That’s a pretty big increase, especially as this increase keeps accumulating as B12 levels drop and homocysteine levels rise.
If you’re a vegetarian, I’m afraid I’ve got bad news for you. A recent study found that 91% of vegetarian test subjects had serum levels of homocysteine measured at 10μmol/l or above. They were nearly all at a greater risk of heart disease, simply because it’s difficult to get enough vitamin B12 in a vegetarian diet without taking supplements.
This might come as a bit of a shock, as normally vegetarianism is considered the healthy option, with vegetarians enjoying longer life expectancy and – most significantly here – a lower risk of cardiovascular disease. This is because the classic signs that someone is likely to suffer heart problems (being overweight, having high blood pressure etc.) are less common in vegetarians.
But strangely, some research has shown that the vegetarians they studied were no less likely to have cardiovascular disease than the control group of meat-eaters. More research is needed to establish a causal link with certainty, but it has been suggested that this apparent discrepancy is due to high levels of homocysteine (caused by vitamin B12 deficiency) effectively canceling out all the cardiovascular health benefits associated with vegetarianism.
Vitamin B12 and Folic Acid
Vitamin B12 and folate/folic acid are inextricably linked (you can read more about that here) and the two compounds work together to break down homocysteine. This means that folate deficiency has the same effect as vitamin B12 deficiency in increasing homocysteine levels and consequently increasing the chances of suffering from heart disease.
Vegetarians and vegans are generally advised to take vitamin B12 supplements, and it’s sometimes necessary to take folate supplements as well. Indeed, one recent study found that while either B12 or folate supplements alone reduced the risk of cardiovascular disease, taking both was significantly more effective than just taking one or the other.
Another relevant problem associated with B12 deficiency is called macrocytosis, a specific enlargement of red blood cells.
Macrocytosis is in turn associated with a number of cardiovascular problems, including strokes, myocardial infarctions, coronary disease and more. Yet more evidence that B12 supplements are a good idea for vegetarians!
In order to prevent vitamin B12 deficiency (and thus reduce the risk of heart disease), key risk groups are advised to take B12 supplements. As mentioned above, it’s best if these supplements also contain folate/folic acid, or you can find tablets that contain both in sufficient quantities.
The primary risk groups are vegetarians and vegans, as well as older men and women (anyone over the age of around 55), patients suffering from pernicious anemia or gastrointestinal disorders, and people who have undergone certain kinds of gastrointestinal surgery.
If you fall into any of these categories, it is vital for your current and future health that you take vitamin B12 supplements, preferably containing methylcobalamin rather than the standard cyanocobalamin (you can read more on that here). We’ve compiled a list of recommended supplements of various kinds (oral pills, sublingual tablets, sprays etc) that you can see here.
A recent US study found that in the long term, it would actually be cheaper to give supplements to everyone at risk of B12 deficiency, than to pay for the inevitable health consequences that occur later in life. When it comes to your body, B12 supplements are a great investment!