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Calcium is the single most abundant mineral in your body, and about 99% of it is found in your bones and teeth. Getting sufficient calcium will help you grow healthy bones and maintain bone density. Focus on eating foods that contain lots of calcium to maintain bone density. The recommended daily intake of calcium varies depending on your age and sex.  Adult men under 70 and women under 50 should get at least 1,000mg of calcium per day. Men over 70 and women over 50 should get at least 1,200mg per day. Pregnant or lactating women should consume at least 1,300mg of calcium daily. Many dairy products such as milk, cheese, and yogurt, are very rich sources of calcium.  If you choose soy milk, almond milk, or other dairy substitutes, look for ones that have been fortified with calcium. Vegetable sources rich in calcium include turnips and collard greens, bok choi, black-eyed peas, kale, and broccoli.  Sardines and salmon are also excellent sources of calcium and omega-3 fatty acids, which are vital for brain health. In addition, they contain vitamin D, which helps your body absorb calcium. Choose whole-grain breakfast cereals that have been fortified with calcium and other nutrients and are low in sugar. Because many people eat these cereals daily with milk, they’re a good, consistent source of calcium. Calcium is also available in dietary supplements. The two main forms are calcium carbonate and calcium citrate. But don’t take calcium supplements without first talking to your doctor because too much calcium can have unpleasant side effects, including the possibility of kidney stones. Vitamin D helps improve your body’s ability to absorb calcium. It's also a crucial component in bone rebuilding. People under the age of 70 should get at least 600IU of vitamin D daily; people over 70 should get at least 800IU daily. Make sure you’re adding foods that contain vitamin D to your diet to help with calcium absorption so you can build strong and healthy bones.  Fatty fish, such as swordfish, salmon, tuna, and mackerel are the best sources of natural vitamin D. Beef liver, cheese, some mushrooms, and egg yolks contain small amounts of vitamin D.  Milk is commonly fortified with vitamins A and D. Many beverages and cereals are also enriched with vitamin D. Spending time in the sunshine is another great way to get vitamin D. Ultraviolet rays trigger vitamin D synthesis in your body, but people who have darker skin produce less vitamin D this way. Use a sunscreen with a broad-spectrum SPF factor of at least 15 whenever you spend time outside.  Vitamin D is also available as a dietary supplement, but talk to your doctor before you take any supplements to make sure they’re safe for you. Magnesium is an important mineral for every part of your body and plays a key role in new bone formation. Eating foods rich in magnesium will make sure that you have enough and will help keep yoru bones dense and strong. Adult men should get at least 400-420 mg per day, and adult women should get at least 310-320 mg per day. Rich sources of dietary magnesium include:  Almonds, cashews, peanuts, and peanut butter Green leafy vegetables like spinach Whole grains and legumes, especially black beans and soybeans Avocados, potatoes with their skins, and bananas A vitamin B12 deficiency may reduce your number of osteoblasts, cells that are responsible for forming new bone. People with vitamin B12 deficiencies are more likely to suffer bone fractures and more rapid bone loss. Fortunately, you can keep your bones strong and healthy by adding foods with vitamin B to your diet. Good dietary sources of Vitamin B12 include:  Organ meats, such as liver and kidney Beef and other red meats such as venison Shellfish, especially clams and oysters Fish, fortified cereals, and dairy products B12 can also be taken as a nutritional supplement as a capsule or sublingual liquid, which makes it easier for vegetarians and vegans to get enough of it. Vitamin C stimulates procollagen and enhances collagen synthesis, which helps your body build bone. Getting enough vitamin C in your diet can increase your bone mineral density, especially if you’re a postmenopausal woman. Adult men should get at least 90mg of vitamin C per day, and adult women should get at least 75mg per day. Good dietary sources of vitamin C include:  Citrus fruits and juices, red and green peppers, tomatoes, kiwifruit, strawberries, cantaloupe, and Brussels sprouts Cabbage, cauliflower, potatoes, spinach, and peas Fortified cereals and other products Most people get enough vitamin C through foods. However, if you need more vitamin C, you can take supplements in the form of a pill or as a powder that can be added to water. Vitamin K increases bone density and may even reduce your risk of fractures. Adult men should get at least 120 mcg per day, and adult women should get at least 90mcg per day. Vitamin K is found in many foods, but good sources include:  Green leafy vegetables such as spinach, kale, broccoli, and collard and turnip greens Vegetable oils, especially soybean oil, and nuts Fruits such as berries, grapes, and figs Fermented foods and cheese Vitamin E is an antioxidant and an important part of a healthy, balanced diet. However, you should be careful about vitamin E supplements; these usually provide more than 100IU per dose, far more than the recommended daily intake of 15mg/22.4IU per day. Consuming too much vitamin E  may decrease bone mass and reduce new bone formation.  Getting sufficient vitamin E from dietary sources is unlikely to pose a threat to your bones, and can provide many health benefits. Good dietary sources of vitamin E include seeds, nuts, plant oils, spinach, broccoli, kiwifruit, mango, tomato, and spinach. Caffeine and alcohol may affect how your body forms new bone and both disrupt the quality of your sleep, which is important for regulating bone mass and density. Avoid drinking too much caffeine or alcohol to help improve the health of your bones and increase their density. If you do decide to drink alcohol, drink in moderation and avoid drinking more than 3 drinks in a 24 hour period.

Summary:
Make sure you’re getting plenty of calcium to keep your bones strong. Add vitamin D rich foods to your diet to help your body absorb calcium. Help your bones repair themselves by eating enough magnesium. Reduce bone loss and fractures by eating foods rich in B vitamins. Consume between 75-90 mg of vitamin C a day. Get between 90-120 mcg of vitamin K a day. Avoid taking vitamin E supplements. Limit the amount of caffeine and alcohol that you consume.