1. Fatigue and fatigue
Calcium participates in muscle contraction activities, which can reduce fatigue and accelerate energy recovery. Due to the loss of bone calcium, the calcium content in soft tissues and blood increases, which will make people prone to fatigue and general weakness.
2. Cramp
Calcium is a good sedative for nervous system. Without calcium, the nervous system will send out abnormal nerve impulses, which will lead to abnormal contraction of skeletal muscle, so middle-aged people are prone to cramp symptoms due to calcium deficiency.
3. Osteoporosis
After middle age, the human body is in a state of negative calcium balance for a long time, which leads to hyperparathyroidism, and the bone is the first to bear the brunt. Due to the continuous release of bone calcium, it leads to osteoporosis and hyperosteogeny.
4. Susceptibility to allergies
Middle-aged people are particularly prone to allergies due to calcium deficiency. Calcium controls the permeability of cells in the body. When calcium is lacking, because there is no correct measure, the body's own immune cells are prone to overreact to external substances and have allergic symptoms.
5, easy to catch a cold
Calcium deficiency in middle age will lead to the decline of physical resistance, and people who often catch a cold should consider whether there is calcium deficiency.
6. Foods for supplementing calcium
(1) Milk
Half a catty of milk contains 3 mg of calcium, and also contains various amino acids, lactic acid, minerals and vitamins, which promotes the digestion and absorption of calcium. Moreover, calcium in milk is more easily absorbed by human body, so milk should be used as the main food for daily calcium supplementation. Other dairy products, such as yogurt, cheese and milk tablets, are good sources of calcium.
(2) Bean products
Soybean is a high-protein food with high calcium content. 5 grams of soybean milk contains 12 mg of calcium, and 15 grams of tofu contains as much as 5 mg of calcium. Other bean products are also good products for calcium supplementation. In addition, experts from Changchun Orthopedic Hospital remind you that soybean milk needs to be boiled for 7 times before it can be eaten. Tofu, on the other hand, should not be eaten with some vegetables, such as spinach. Spinach contains oxalic acid, which can combine with calcium to form calcium oxalate conjugate, thus hindering the absorption of calcium by human body, so tofu and other bean products are not suitable for cooking with spinach. However, if bean products are cooked with meat, they will be delicious and nutritious.
(3) kelp and shrimp skin
kelp and shrimp skin are high-calcium seafood. If you eat 25 grams a day, you can get 3 milligrams of calcium. And they can also reduce blood lipids and prevent arteriosclerosis. Kelp cooked with meat or cooked in cold sauce is a good food. Shrimp skin contains more calcium, and 25 grams of shrimp skin contains 5 mg of calcium. Therefore, it is a good choice to make soup or stuffing with shrimp skin.
(4) Animal bones
More than 8% of animal bones are calcium, but it is insoluble in water and difficult to absorb, so you can break it in advance when making food, add vinegar and cook it slowly with slow fire. When eating, remove the oil slick and add some vegetables to make a delicious soup.