In one sentence, describe what the following article is about:

Adults should be getting 1,000 mg of calcium every day. Calcium is the most important mineral for maintaining bone health, because bones use calcium to remain strong and prevent bones from becoming brittle. Men over 50 and women over 70 need more calcium – 1,200 mg per day.  Foods high in calcium include dairy products, broccoli, salmon, leafy green vegetables, soy products, and cheese. You should not consume more than 2000 mg of calcium a day. Side effects of calcium supplementation include constipation, indigestion, and increased risk of kidney stones. Scientists are still figuring out how much vitamin D is optimal in a diet, but you should get at least 600 international units per day. Healthy teens and adults can have up to 4,000 IU per day. The main way to do this is by getting sunlight. If you cannot get sunlight, talk to your doctor about other ways to get vitamin D. The use of vitamin D supplements is controversial, so your doctor may offer specific advice. This doesn’t mean tanning, which is quite unhealthy for your skin and can cause cancer. It only takes a short time to get enough vitamin D – as little as 15 minutes depending on your skin type and where you live. A healthy diet includes a balance of lean protein, whole grains, and fruits and vegetables. Trace amounts of these elements have been shown to be prevalent in bones. There are foods you can eat to increase your levels of manganese, zinc, and copper.  Foods high in manganese include nuts, shellfish, dark chocolate, soybeans, and sunflower seeds. Beef, shellfish, and peanuts are foods that are high in zinc. Copper is prevalent in foods like calamari, lobster, sun dried tomatoes, and oysters. The body needs to remain hydrated to be healthy. Hydration benefits your entire body, especially your organs and joints, and has been shown to reduce the risk of osteoporosis. The amount of fluids you need is based on various factors, but women should generally have nine cups per day, and men 13. Having at least eight on any given day is good, but try for more. Salt, soda, carbonated drinks, caffeine, and hydrogenated oils should be consumed in moderation. They are known to diminish calcium content in bones. They have numerous other drawbacks for your health, so it is best to avoid them in most situations. You should be consuming a maximum of 5,000 IUs (international units) of Vitamin A per day. To avoid consuming too much Vitamin A, eat fewer eggs or egg whites only, switch to non-fat or low-fat dairy products and check the concentration of Vitamin A in your multivitamin supplements. This compound is important to bone growth, but too much actually contributes to bone loss. Teenage and adult males should get about 3,000 IU of Vitamin D, and teenage and adult females around 2,310. For your reference, an ounce of cheddar cheese contains about 300 IU of Vitamin A, and a cup of whole milk 500.

Summary:
Consume foods and drinks high in calcium. Get plenty of vitamin D. Eat a healthy diet rich in manganese, zinc, and copper. Drink at least eight glasses of clean water every day. Avoid excessive amounts of harmful substances. Consume the right amount of Vitamin A.