Supplements are probably unnecessary in most healthy children who are offered a good diet. If you were to mention a couple though - athletes will benefit from a 1000-1300 mg calcium supplement with Vitamin D between 600-1000 IU (international units) per day if they don’t get it during their normal diet. Be sure tho check with your doctor as dose recommendations do change.
Calcium and Vitamin D are important for bone health. Because Vitamin D helps with calcium absorption, it’s best to take them together. Too much calcium in any form can result in kidney stones, as well as potential calcium deposits causing vascular and heart problems, so more is not necessarily better. Athletes with kidney stones, hyperparathyroidism, or urine abnormalities should check with their health care provider before starting a calcium or Vitamin D supplement. For every athlete, avoiding soft drinks high in Phosphorus (dark colored regular and diet drinks which might steal calcium from your body - this is controversial) is best, replacing them with milk, fruit juices, Gatorade with low sugar, and water.
Vitamin D has become a “hot topic”, not only for improved bone health, but also as a potential benefit to the brain. It also may decrease the risk of some cancers, and perhaps decrease chronic pain and some forms of depression. It is a vitamin many health care providers are checking labs in their patients (25-OH Vitamin D), and supplementing when found low, below 30. Prescriptions up to fifty thousand IU of Vitamin D3 once weekly for several months is a treatment used in those patients with lowest levels while doses of 5000IU of Vitamin D3 per day may be considered for those with moderate insufficiency. We get Vitamin D from food, such as milk and fish, and also from sunlight. You can’t get too much Vitamin D from the sun (but you can get a sunburn and skin cancer so 10 minutes or so of sunlight without skin protection is probably enough). People living north of 37 degrees latitude (Tulsa, OK) likely don’t get enough vitamin D from sun during the winter season (what may cause Seasonal Affective Disorder (SAD) in some people). Too much vitamin D in foods or supplements can cause diarrhea and too much calcium, may increase the risk of kidney stones and calcium deposits in the vascular and cardiac system. Some health care providers believe D2 is adequate while many believe D3 is superior. Again, check with your health care provider if a supplement is necessary and what dose is best for you.
What About Other Supplements?
There is a lot of media attention (and salespeople) interested in selling you other vitamins. Hot topics include iron for runners, fish oil for the heart, probiotics for the intestines, and mangosteen for the immune system. While none are likely dangerous, they are also probably unnecessary (and expensive) if you already have a good diet! Research is constantly being done to prove effectiveness or danger with too little or too much of a vitamin or mineral. It can be difficult for even your health care provider to keep up!
Bottom line - athletes, even more so than non-athletes, need food! And vitamins DO NOT contain calories! Eating right is most important, adding supplements might be considered in those that can’t achieve optimal nutrition with eating.
The constant media attention on eating right, fad diets, and not eating so much is directed towards the non-athlete. And while the American public indeed has a greater percentage of unhealthy, obese people at risk for diabetes II, hypertension, and high cholesterol - the great majority of young athletes need healthy calories for continued growth and muscle/bone strength. The media also promotes tiny, fatless models that may mislead young athletes in believing the less you weigh the better. On the contrary, calories help athletes achieve stronger bones and increased muscle - all which must weigh something!