Author: Carol Simontacchi, CCN, MS
Similar mechanisms may be at work in food cravings although clinicians note that deficiencies in certain minerals may trigger carbohydrate/sugar cravings.
Five minerals (and their co-factors) are critical for adequate blood sugar control: chromium, magnesium, manganese, zinc, and vanadium. Chromium is a cofactor with insulin and is essential for normal glucose utilization, for growth, and for longevity, working hand in hand with nicotinic acid and glutathione. Chromium is required for normal fat and carbohydrate metabolism.
Manganese is also associated with sugar and fat metabolism. Studies show that manganese-deficient rats exhibit reduced insulin activity, impaired glucose transport, lowered insulin-stimulated glucose oxidation and conversion to triglycerides in adipose cells. Deficiencies in manganese lead to lessened insulin sensitivity in fat tissue and a decreased ability to transport glucose through the blood and metabolize it for energy.
Magnesium is part of over three hundred enzymes in the body but also helps maintain tissue sensitivity to insulin, helps control glucose metabolism, and participates in the regulation of insulin.(1)
Interestingly, clinicians often note that magnesium deficiency leads to sugar cravings and chocolate cravings that disappear as soon as magnesium levels are brought back to normal. Because large amounts of magnesium are found in the hippocampus (the “emotional, thought and memory center of the brain”), (2) deficiencies may form the emotional environment which encourages carbohydrate cravings.
A number of both animal and rat trials have shown that stress triggers chocolate cravings, which may in turn be related to noradrenaline and dopamine levels in the brain.(3) (4)
Dopamine has been called the “pleasure neurotransmitter” and evidence shows that dopamine is a magnesium-dependent neurotransmitter.(5) It is possible that low levels of magnesium trigger low levels in dopamine in the brain, possibly triggering desires for chocolate as a biological attempt to increase dopamine and thus increase pleasure.
Although chocolate is a food which provides pleasure, for those who consider intake of this food to be excessive, any pleasure experienced is short lived and accompanied by feelings of guilt.”(6)
While magnesium appears abundantly throughout the food chain, Americans seem to be taking in far less than the recommended DV (400 mg/day). One author noted that up to three-quarters of the population may consume less than DV levels, and if studies on magnesium status were done on dieters, that figure may jump to 100%.(7)
Vanadium, in the form of vanadyl sulfate, mimics the activities of insulin. While chromium potentiates insulin, vanadyl is biologically active even in the absence of insulin, significantly increasing liver glycogen and improving the uptake of glucose by muscle tissues. It inhibits the storage of excess calories from carbohydrates as fat by stabilizing the body’s production of insulin.(8)
Zinc is also essential to blood sugar regulation by influencing carbohydrate metabolism, increasing insulin response, and improving glucose tolerance. Zinc influences basal metabolic rate, thyroid hormone activity, and improves taste sensitivity.(9)
The average American diet is already deficient in these minerals but in frequent dieter even more so! It has been noted that zinc deficiency is common in undeveloped countries (10) but the diets of many Americans, particularly dieters, is no better. The best sources of zinc include oysters and red meat, neither of which is eaten frequently by many people. The average American consumes less than 10 mg of zinc per day, far less than what is required for normal sugar metabolism or the other functions of zinc in the body.
Because it is likely that mineral deficiencies are widespread, particularly in the dieting population, it is important that some assessment of mineral status be made. Correcting mineral deficiencies can go a long way toward helping the frustrated dieter control her impulses to eat something sweet, something fatty, or something devoid of nutrition in an attempt to satisfy an inner compulsion.
1. Seelig, Mildred S., MD, M.P.H., F.A.C.N., Magnesium Deficiency in the Pathogenesis of Disease, Plenum Medical Book Company, NY, 1980, p. 262.
2. Pfeiffer, C. Carl, Ph.D., MD., Mental and Elemental Nutrients, Keats, CT, 1975, p. 24.
3. Willner, P., Benton, D., Brown, E., Cheeta, S., Davies, G., Morgan, J., Morgan, M., Depression increases “craving” for sweet rewards in animal and human models of depression and craving. Psychopharmacology, 136(3):272-83, 1998 Apr.
4. Amyard, N., Leyris, A., Monier, C., Frances, H., Boulu, RG, Henrotte, JG., Brain catecholamines, serotonin and their metabolites in mice selected for low (MGL) and high (MGH) blood magnesium levels. Magnesium Research, 8(1):5-9, 1995 Mar.
5. Antonelli, T., Govoni, BM, Bianchi, C., Beani, L., Glutamate regulation of dopamine release in guinea pig striatal slices. Neurochemistry International. 30(2):203-9, 1997 Feb.
6. MacDiarmid, JI., Hetherington, MM., Mood modulation by food: an exploration of affect and cravings in ‘chocolate addicts’. British Journal of Clinical Psychology. 34(Pt 1):129-38, 1995 Feb.
7. Altura, Burton M., Ph.D., et al., Magnesium: growing in clinical importance. “Patient Care,” January 15, 1994;130-136. As cited in Clinical Pearls 1994, pg. 329.
8. Clouatre, Dallas, Ph.D. Getting Lean with Anti-Fat Nutrients, Pax Publishing, CA, 1993), p. 22.
9. Groff, James L., Sareen S. Gropper, Sara M. Hunt. Advanced Nutrition ad Human Metabolism. West Publishing Company, MN, 1995, 373.
10. Sandstead, Harold H., M.D., and Alcock, Nancy W., Ph.D., Zinc: an essential and unheralded nutrient. Journal of Laboratory and Clinical Medicine, 197;130(2):116-118. As cited in Clinical Pearls 1997 pg. 271.