The Role and Functions of Calcium for Human Health - Essay Example

Calcium Intake & Weight Loss Introduction: In developed countries there is evidence to suggest that the leading cause of death is related to the diet of the individual, and in addition to this it is also the exacerbating factor for many of the diseases that are associated with eating habits like hypertension, diabetes mellitus and obesity. This has led to dietary concerns in the control of these diseases. In addition a slim body has become a social obsession in developed societies, especially in young women, and this has led to greater emphasis on food intake, or rather a reduction of it in an attempt to retain a slim body. The concern in any dietary restriction is making available to the body the minimal requirement of all the essential nutritional factors, and the influence of these factors on the weight loss being attempted. Calcium is an essential mineral requirement of the body, and also has a role in metabolism. Dietary calcium intake is a significant factor in weight loss. Overview: Calcium is the cation that is found in the largest quantities in the human body, and the reason for this is that it plays a significant role in many functions of the body including the neuromuscular function. Diary products are the most important source of calcium for the human body. Vegetables like peas, beans, pulses, potatoes, and cauliflower are the other likely sources of calcium for the human body. Vitamin D plays a significant role in the absorption of calcium by the human body. Ninety nine percent of it is stored in the body in the bones and teeth, and the skeleton can be considered as the storehouse of calcium in the human body. Inadequate availability of calcium in the human body leads to calcium being leached from the bones and teeth, and osteoporosis is a serious concern in the lack of adequate supply of calcium to the human body. The normal daily intake of calcium in adults is required to be about 1Gm per day, with about 100-250 mg of calcium being excreted daily in the case of a normal adult. Current estimates show that the average intake is around 600 milligrams per day. Calcium is required for bone formation in the young. Calcium plays a significant role in neuromuscular excitability of the voluntary and involuntary muscles. It also has a vascular role to play, and that is in the clotting of blood, and in the maintenance of capillary permeability. In women calcium requirement is even higher, especially in the case of pregnant and lactating women. The average intake of calcium in girls in America during puberty is already believed to be below the desirable levels. Osteoporosis is a worldwide concern, and more so in women, where the incidence of osteoporosis is six times more than in men. (1). Dietary practices around the world have a concentration on high protein-low carbohydrate diets, without paying enough attention to the normal body requirements of minerals like calcium, or the added benefit that calcium provides in the weight loss program itself with its role in metabolism. (2). Literature Review: There is evidence that suggests dietary calcium has a key role to play in regulating energy metabolism. Diets rich in calcium attenuate adipocyte lipid accretion and weight gain, when the diet is energy rich, and increases lipolysis and preserves thermogenesis, when there is a restriction of calories, like in a weight loss program. This action of dietary calcium thus accelerates weight loss during a weight loss program. In addition it is seen that increased calcitriol released, when there is inadequate dietary calcium, causes stimulation of calcium ion influx into human adipocytes, resulting in promoting adiposity. Thus suppression of calcitriol levels by adequate, or increased dietary calcium intake should be a target in dietary plans for weight loss programs. (3) There have been several epidemiological studies that have looked into the link between the prevalence of obesity, and dietary intake of calcium. Analysis of the data of the National Health and Nutrition Examination Study III (NHANES III) showed that after taking into consideration the impact of energy intake and physical activity, body fat was found to be lower in individuals with the highest dietary intake of calcium. The lowering of body fat corresponded to the increased intake of dietary calcium, and at the recommended daily average for calcium, the risk of obesity dropped by 85%. Another study that looked into the link between calcium intake and bone density, also found that women with an intake of the daily recommended average for calcium had an overweight prevalence rate of only four percent, and concluded that average yearly reduction in weight gain was linked to the increased intake of dietary calcium. (4) Zemel et al (2004) conducted a research study with the objective of determining the effects of increased dietary calcium, when there was a restriction placed on the intake of calories. Thirty two obese patients were selected and maintained for 24 weeks on a balanced diet, and randomized to a standard diet of 400 to 500mg of calcium per day supplemented with placebo, or a high calcium diet supplemented with 800mg of calcium per day, or a high-diary diet consisting of 1200 to 1300 mg of dietary calcium per day, supplemented with placebo. Patients assigned the standard diet were found to have lost 6.4% +/-2.5% of their body weight. In the high-calcium diet subjects the weight loss was found to be 8.6% +/- 1.1% of their body weight, and in the high-diary diet it was 10.9% +/- 1.6% of their body weight. Another important aspect of the findings was that fat loss was similarly increased in the high-calcium and high-diary diets by 38% and 64% respectively, and there was a similar picture in the comparison of the weight loss in the trunk region of the body. On the basis of these findings, in the discussion, the authors of the study say that increased dietary calcium significantly enhances weight and fat loss during calorie restriction, and an increased percentage of fat loss is from the trunk region of the body, with diary products providing an even greater impact on weight and fat loss. (5) In another study conducted on the impact of diary products consumption on obese African Americans, there were thirty-four subjects in the first of the randomized trials. They were maintained on a low calcium intake of 500mg per day, or low diary less than one serving per day, or a high diary diet, which included 1200 mg of calcium per day, and three servings of diary products, with no change in energy or macronutrient intake extending for twenty-four weeks. In the second trial involving weight loss, twenty-nine subjects underwent a similar randomized trial of low or high diary diets, with the added feature of a caloric restriction regimen (500Kcal/day). The results of the first trial showed that while the body weight remained stable in both the groups during the maintenance period, the high diary diet led to a decrease in total body fat of 2.16 kg, of which the trunk fat loss was 1.03 kg, and there was no significant fat loss in the low diary products group. In the second trial it was found that both diets produced a significant loss in weight and fat, but the weight and fat loss was nearly two fold higher with the high diary products group, and loss of lean body mass was significantly lower in comparison with the low diary product group. In their discussions the authors say that substitution of calcium-rich foods, when isocaloric diets are used reduces adiposity, and improves the metabolic profiles in obese African Americans in the absence of energy restrictions, and that the weight loss and fat loss is enhanced in the presence of energy restrictions. (6) Conclusion: Calcium is an important mineral requirement for the human body. Calcium has a role to play in regulating energy metabolism. There is evidence to suggest that this function of calcium is significant for weight loss programs. An intake of 1.0 to 1.2 grams of calcium every day has been found to be of assistance of in weight loss programs and more so as the a larger part of the weight lost is in the trunk region of the human body, as a result of the calcium intake. Thus dietary calcium intake is a significant factor in weight loss. Works Cited 1. Anitia, F. P., & Abraham Phillip. Clinical Dietetics and Nutrition. Oxford. OXFORD UNIVERSITY PRESS. Fourth Edition. 2002. 2. Blackburn, L. George. “Making Scientific Sense of Different Dietary Approaches, Part 2: Evaluating the Diets”. Medscape Diabetes & Endocrinology. 2004. Medscape Today. 3 Nov. 2006. . 3. Zemel, M. B. “Regulations of adiposity and obesity risk by dietary calcium: mechanism and implications”. Journal of the American College of Nutrition, 21.2 (2002): 146S-151S. 4. Schrager, Sarina. “Dietary Calcium Intake and Obesity”. Journal of the American Board of Family Practice, 18.3 (2005): 205-210. 5. Zemel, M. B. et al. “Calcium and dairy acceleration of weight and fat loss during energy restriction in obese adults”. Obesity research, 12.4 (2004): 582-590. 6. Zemel, M. B., Richards, J., Milstead, A., & Campbell, P. “Effects of calcium and dairy on body composition and weight loss in African-American adults”. Obesity research, 13.7 (2005): 1218-1225. Read More