This is part of the series of notes for The Everything Diet (see introduction here).
Thiamine, also known as vitamin B1, is the name given to the nutrient that prevents and cures beriberi – a malnutrition disease that can make people absolutely miserable and eventually kill them if not addressed.
Our bodies use thiamine for a great many processes. One of the best-understood of those processes is as part of an enzyme (thiamine pyrophosphate) that our bodies need to metabolize carbohydrates and proteins.
Without sufficient thiamine, a person can develop deficiency symptoms, which include peripheral neuropathy (tingling and numbness in the extremities), edema, muscle atrophy, nausea, vomiting, and heart complications, among others.
Obviously, inadequate dietary intake of thiamine is a major cause of thiamine deficiency. But other factors can and do contribute.
Chronic alcohol abuse can produce thiamine deficiency because it can greatly reduce absorption of the nutrient. Alcoholism is commonly associated with forms of thiamine deficiency.
Other factors that can play a role in thiamine deficiency are thiamine antagonists, which include sulfites (used as food preservatives), many types of raw fish and shellfish, and some constituents of plant foods (tannins and some bioflavonoids).
However, when it comes to thiamine antagonists, as best I can tell, these are only a problem when consumed in very large amounts by people with marginal thiamine status. So there’s really no reason for most people to be concerned about eating sushi and drinking a cup of coffee, even on a regular basis, as long as thiamine intake is sufficient.
Thiamine supplementation is typically in the form of thiamine mononitrate or thiamine hydrochloride. And while these forms do effectively reverse most if not all symptoms of thiamine deficiency, it is difficult to know if these forms achieve everything in the human body that thiamine from foods can achieve.
The RDA (recommended daily allowance) for thiamine is 1.1 mg for women, 1.2 mg for me, and 1.4 mg for pregnant and lactating women.
The two best food sources of thiamine are pork and wheat germ. Some non-fortified nutritional yeast supplies very large amounts of natural thiamine as well.
Three ounces of pork tenderloin provides 0.81 mg of thiamine while half a cup of wheat germ provides about 0.9 mg of thiamine.
Other good sources include sunflower seeds, asparagus, green peas, Brussels sprouts, beans, whole grains, sweet potato, and many types of fish.
It’s not terribly hard to meet thiamine needs as long as a person eats a sufficient quantity of a sufficient number of these good sources of the nutrient.
However, it’s not difficult to see how many restrictive diets could shortchange a person on thiamine. For example, a strict Paleo diet that eschews grain, seeds, and beans/peas, could put a person at risk for deficiency if the person also does not eat pork or much fish. (And many people do avoid pork and fish for all kinds of reasons.)
And while there is absolutely no need to be worried about thiamine antagonists in most cases, if a person’s thiamine intake is marginal or below needs, excessive intake of coffee (also common among some Paleo circles) could hasten and worsen thiamine deficiency.
So again, a diverse and inclusive diet is a powerful and relatively easy way to ensure that you can meet your thiamine needs naturally and still enjoy coffee or tea or sushi.