Often, when I suggest a multivitamin supplement to patients, I am told “Vitamins make me hungry”. For people who are trying to watch their weight, this is a significant concern.
I’ve always been intrigued by nutritional aspects of health, though, and the recent controversies about the role of vitamin D in cancer prevention have piqued my interest still further. I’ve started screening more patients for Vitamin D levels and an awful lot of the population is deficient.
Additionally, I am intrigued because of personal experience – recently my metabolism has seemed very slow; my energy levels are low and my weight ballooning despite regular exercise. My ability to improve my athletic performance has been crappy, too. At a recent vacation, I ate reasonably, exercised a lot (average 5 miles brisk walking in hilly territory daily) and still managed to gain 5 lbs in a week. Then, I started taking a prenatal vitamin around a week ago (am not pregnant) and am finding that my appetite has been very, very lively since taking it. So, curious how that increased hunger was affecting the weight gain, I stepped on my scale this AM – and found that extra 5 lbs was gone along with a few more.
So of course I got curious. Maybe vitamins make me hungry, but also increase my metabolic rate? I hit the library.
Turns out there’s intriguing stuff out there about the role of micronutrients in energy metabolism. Zinc deficiency, for example, is associated with metabolic slowing and difficulty with athletic performance. And zinc’s one of those nutrients that is a little hard to get unless you eat lots of red meat. I looked at my prenatal vitamin – nearly 200% of the US RDA in zinc. Hmmm. The old Centrum-like vitamins I used to take have about half that. Iron deficiency also may be associated with metabolic slowing, and again a prenatal vitamin is likely to supercharge me with iron. Thiamin is essential for healthy carbohydrate metabolism. Riboflavin is involved in mitochondrial function, which links directly to metabolic activities. Pantothenic acid, Niacin, Biotin, Vitamin D, and calcium all seem integrally tied up in metabolic rate… as do microelements like selenium, cobalt, mylybdemum, manganese, chromium, and phosphorus. And it appears if you’re regularly physically active, your need for all of those elements is higher.
A week’s experiment on myself hardly makes for a scientific finding. And the medical literature is astoundingly thin on info about the relationship between micronutrients and metabolic rate, or micronutrients and athletic performance. But having winnowed out what studies exist, I’m very intrigued. I think I will start pushing my patients to take the vitamins even though they get hungry – because if the vitamins speed their metabolism and increase their available energy, they’ll be a lot more likely to be healthy! And me, I think I’ll keep taking that prenatal vitamin no matter whether I decide to reproduce or not….