What Should Be My Daily Calcium Intake?

Calcium is quite abundant. However, most of these calcium are insoluble calcium compounds, and calcium can be absorbed by the human intestinal tract only when it is ionic water-soluble calcium. Usually, only about 30% of the calcium in the food we eat every day can be absorbed by the intestines. Moreover, the calcium content in our diet is not high, and the situation of calcium deficiency in the body is called calcium hunger. Calcium hunger can cause osteoporosis, osteoporosis, rickets in children, hand and foot tics, and hypertension, kidney stones, and colon cancer.

Calcium is a macro element constituting the human body, ranking fifth in abundance. In addition to calcium, which constitutes hard tissues such as bones and teeth to support the body and chew, calcium transmits information on nerve impulses, excitability of muscle cells and normal heart beat, promotes blood clotting, maintains normal capillary osmotic pressure, and acid-base balance in the body Life activity plays a pivotal role in regulating and controlling, shouldering the task of second messenger regulating and controlling the life activity of human cells, and is a cell life activity initiating and regulating agent. Without calcium, life activities will stop; lack of calcium, physiological activities and diseases will occur in life activities.

According to a survey in Shanghai, the average daily calcium intake per resident is only 570.4 milligrams for urban residents, only 387.3 milligrams for rural residents, and 510.5 milligrams for the entire city. The calcium intake is only 85.3% of the standard supply. In other words, the calcium intake of residents in Shanghai is only a little over half of what the human body needs. Studies have shown that people spend their lives under severe calcium starvation, especially the elderly, infants, pregnant women, and nursing mothers. Due to low dietary intake, the intestinal absorption function and renal absorption ability are far less than young adults, or Physiological requirements are high, and the phenomenon of physiological calcium overdraw is more prominent. Due to the lack of calcium, the human body is in a state of negative calcium balance, and physiological calcium overdraft occurs, resulting in a decrease in blood calcium levels. When it drops to a certain threshold, it will cause parathyroid hormone to be secreted.

Parathyroid hormone has a osteoclasting effect, which reversely extracts calcium from bones to maintain blood calcium levels. When the degree of calcium deficiency is relatively mild in the early stage of calcium deficiency, reversible physiological abnormalities only occur, such as cardiac ventricular premature beats, emotional instability, and decreased sleep quality. Persistent hypocalcemia, especially after middle age, the human body has been in a state of negative calcium balance and hyperparathyroidism for a long time. The first is the bone. The continuous release of large amounts of bone calcium leads to osteoporosis and osteogenesis, bitterness. Unspeakable. On the other hand, in the case of continuous increase in parathyroid hormone, because parathyroid hormone can promote the opening of calcium channels on the cell membrane and cannot be closed, and inhibit the calcium pump, making the calcium pump function weak, causing the cells to be calcium The inflow to the cell stops and cannot stop, which should pump too much calcium out of the cell out of the cell but not out. Due to the abnormal calcium influx of the cells, the cells have an abnormally high calcium state in the cells. Sustained intracellular high calcium state will excite cells like uncontrolled wild horses, which leads to uncontrolled hyperactivity, resulting in abnormal cell physiological activities, continuous abnormal activities causing energy depletion, and waste generated during metabolism cannot be removed in time, posing self-injury. As a result, the cells tend to die of abnormal calcification. Due to calcium deficiency, osteoporosis, osteoporosis, rickets in children, hand and foot tics, and hypertension, kidney stones, and colon cancer occur.

The absorption of calcium is affected by many factors. When the calcium intake level is different, the apparent absorption rate is very different. Under the condition of "calcium starvation", the absorption rate is significantly increased. The appropriate calcium intake for rats is calcium in the feed. Between 3000 and 5000 mgkg, there is too much calcium supplementation, and the calcium absorption rate is reversed. On the basis of low calcium feed (0.15% Ca), 0.35% calcium supplementation can meet the growth needs of rats, which is consistent with reports from SATIO et al. . When the ratio of CPP to Ca was 1.0 and 2.0, the body weight of the two groups of rats was significantly higher than that of the low-calcium control group and the calcium-supplemented group after 4 weeks, and the calcium absorption and retention rates were also significantly higher than those of the calcium-supplemented group. Based on meeting the physiological requirements of calcium in rats, the appropriate dose of CPP can better promote calcium absorption and utilization.

China's dietary structure has a large proportion of plant-based foods, and the lack of dairy products can easily cause calcium deficiency, which seriously affects the health of children, pregnant women, nursing mothers, and elderly with reduced physiological functions. In addition to the inadequate calcium intake, malabsorption is a major factor that cannot be ignored. The premise of calcium absorption in the small intestine is to maintain the dissolved state, but the middle and lower part of the small intestine is a neutral to weakly alkaline environment. It is easy to cause insoluble precipitation of calcium and reduce the absorption rate due to the interference of various factors. Therefore, merely strengthening the absolute content of calcium in food is not enough to solve the problem well. Increasing the absorption promotion factor and improving the absorption utilization rate are more effective ways. ^[1]

Calcium starvation hypertension

Calcium can regulate heart rhythm and blood pressure, and is also a vasoconstrictor. Calcium deficiency causes abnormal calcium influx, leading to abnormal accumulation of calcium in the inner wall cells of blood vessels and smooth muscle cells, causing vasoconstriction, increased peripheral resistance of blood vessels, and abnormally increased blood pressure. Continued calcium inflow promotes calcification and degeneration of elastic fibers and endothelial cells in the blood vessel wall, and even cracks and breaks. Peripheral resistance further increased, and blood pressure continued to rise. Due to the damage to the inner wall of blood vessels, lipid permeability increases, and blood lipids infiltrate the damaged parts of the blood vessel wall, causing cholesterol and other lipid substances to deposit on the blood vessel wall. Vascular endothelial cells are injured and secrete endothelin and certain activating factors, causing platelets and leukocytes to wither and aggregate on the vessel wall. The injury of vascular endothelial cells, in turn, activates a compensatory physiological response, which promotes abnormal proliferation of vascular smooth muscle and fibroblasts and subendometrial displacement, resulting in thickening and hardening of the arterial wall, so layers of atherosclerosis Specimen hardening formed. Studies have shown that for some patients with hypertension, increasing the amount of calcium preparations without using drugs can help control hypertension. James H. Dewell, associate professor of preventive medicine at the University of Southern California School of Medicine, calculated the results of a 31-year survey at the National Statistical Center and found that people who use 130 mg of calcium per day People have a 21% lower rate of hypertension and a 52% reduction in risk among people under the age of 40.

Coronary heart disease

Many studies have shown that calcium has another way to protect the heart from harm, which is to help lower cholesterol levels in the blood. It has been observed that men with higher cholesterol levels eat low-calcium foods for 10 days (401 mg of calcium per day) and check their cholesterol levels; then let them eat high-calcium foods (2200 mg of calcium per day). Results High-calcium foods could reduce total cholesterol by 6%, of which LDL was reduced by 1%. What's more important is that the amount of HDL is unchanged. Experts believe that taking a large amount of calcium can help reduce cholesterol and prevent coronary heart disease ^[2] .

Calcium hungry urinary stones

For years, doctors told patients with kidney stones to limit calcium consumption. The reason is that calcium is a major component of stones, but new research that has caused controversy suggests that the method of reducing the risk of kidney stones is precisely to increase calcium intake. Everyone knows that diet, especially vegetables, contains a large amount of oxalate. The human body cannot use oxalate. Generally, it is combined with calcium in the intestine to form calcium oxalate and excreted in feces. Inadequate intake of calcium in the diet will cause excess oxalate to be absorbed through the intestinal lumen and into the blood, eventually being excreted by the kidneys. If the human body is in a state of negative calcium balance for a long period of time, kidney cells will inevitably suffer from abnormal calcium influx, impaired renal reabsorption, and increased urinary calcium excretion. High calcium urine combines with oxalate in the urine to form large and small calcium oxalate stones. If calcium is not to be avoided, but calcium supplementation measures are taken, especially water-soluble calcium supplements, then the oxalate in the gastrointestinal tract is combined with the diet to form calcium oxalate and excreted in the feces. In addition, supplementing with a sufficient amount of calcium can reverse the negative calcium balance, normal renal reabsorption function, decreased urinary calcium excretion, and reduced the possibility of stones. Dr. Carrie C. Colhan and his colleagues at Harvard School of Public Health conducted a follow-up survey of 45,510 men with no history of kidney stones and found that people who had more calcium in their diet (average of 1,320 mg per day) were more likely to use calcium People with a small amount (156 mg / ) are one-third less likely to develop urinary tract stones.

() Calcium Starvation (Straight) Bowel Cancer

A high-fat diet will over-stimulate the secretion of bile. Excess fatty acids and bile acids are triggers for canceration of colon (straight) intestinal cells. Studies have shown that patients with colorectal cancer have a serum bile acid content about 1 times higher than that of normal people, and cancerous cells have a bile acid content that is more than 3 times higher than normal cells. If mice are fed with a high bile acid diet, the incidence of colonic (straight) intestinal cancer is significantly increased. If a sufficient amount of calcium carbonate is added, calcium ions are combined with fatty acids and bile acids to form insoluble fatty acid calcium and bile acid with feces. Excretion, thereby eliminating the triggering factor of canceration, proving that calcium can indeed inhibit intestinal cell canceration.

Calcium Hunger

This disease is due to the lack of vitamin D in the body, causing intestinal absorption of calcium and phosphorus. In addition, due to the inability of the parathyroid glands to secrete more parathyroid hormones in time, the blood calcium is reduced, which increases the excitability of neuromuscular muscles, generalized convulsions, hand and foot spasms, and laryngeal spasms. Time suffocation, causing ischemic hypoxic brain damage. According to medical observations, the brain nerves are most sensitive to ischemia and hypoxia. Asphyxia for 10 seconds, neural function begins to appear impaired. For several minutes after asphyxia, irreversible damage to the blood vessels and nerves will occur, which will affect children's intelligence in light, and cause low energy, dementia. Therefore, it is very important to prevent hand, foot and twitch drowning. Children who are breastfeeding or artificially fed must have sufficient calcium. In addition to calcium supplementation, outdoor activities should also be increased, more sun exposure, and adequate vitamin D supplementation to prevent the occurrence of hand, foot and twitch drowning.

Calcium starvation osteoporosis

Osteoporosis is another serious consequence of negative calcium balance caused by chronic calcium deficiency. Many studies have shown that increasing calcium intake has an important role in reducing bone loss, and it also plays an important role in reducing the rate of bone fractures caused by osteoporosis. Especially when taking vitamin D while taking calcium, the effect is particularly obvious. Many experts believe that calcium supplementation should begin at puberty, when bone is forming and the effect will be better.