Calcium and Vitamin D: How Much Is Enough?

Learn the recommended daily intake for both based on your age—and lower your risk of osteoporosis.

All of us want to prevent osteoporosis, but how? More milk? More calcium? More vitamin D? Supplements? 

Recent research has brought up questions about our daily calcium intake and how much we really need. However, the issue is more nuanced than that. We have to consider the recommended dose for vitamin D separately, as it involves different research and recommendations, and many of us are deficient. 

Regarding calcium, studies have shown that people with the very lowest intakes do appear to have a higher fracture risk. However, finding a connection between higher daily calcium intake and stronger bones has been hard for experts to prove.   

Most studies depend on adults remembering how much calcium they had as a child 30 to 40 years ago, and then studying their current bone density—and these studies have shown no benefit to drinking extra milk in childhood. One study showed that drinking higher amounts of milk as an adult may actually be associated with an increased risk of fractures. It’s important to know that this particular study was not saying milk led to the fractures, however, just that people who drank more milk as adults were also more likely to have fractures. All that to say, extra milk consumption hasn’t yet been shown to benefit adult bones. 

What's more, taking calcium supplements as an adult has been associated with small possible increases in coronary disease (but possibly only if you take them with food) and kidney stone risk. 

What about vitamin D supplements? Research has shown that many of us are deficient due to diet, less sun exposure and a variety of other factors. While some researchers see the benefit of vitamin D supplementation, especially for certain age and deficiency groups, there’s no across-the-board agreement. 

Where does that leave us? How much you need depends on your age group and health status. However, there are a couple of facts that are true for everyone: 

  • Calcium from your diet and calcium from supplements is not the same thing. In fact, your body does not use them in the same way. Notably, dietary calcium reduces your risk of kidney stones, while supplemental calcium increases it. Getting as much of your calcium and vitamin D needs met from your diet is ideal, with supplementation only when necessary. 

When looking for high calcium foods, the richest sources are milk, calcium-enriched non-dairy milks (such as soy milk), plain yogurt and hard, waxy cheeses such as cheddar and Swiss. Some tofu and cereal options are high in calcium, too, and contain 15 percent of the daily value (150 milligrams or mg) or more per serving. Always check your food labels to be sure. 

  • Certain lifestyle habits are important for bone health. Exercise is proven to improve bone mass, while excessive carbonated beverages, smoking and alcohol all lower bone mass. 

That's a lot to take in, right? So, where does that leave us? Here is my daily calcium recommendation, as well as how much vitamin D you need at each age for your bones and your overall health: 

Age 10 to 30 in good health 
The second and third decades of life are times of peak bone building. Once you hit 30, the amount of bone you have is your maximum, and it will only decrease from there. That’s why adequate calcium and vitamin D from 10 to 30 is crucial. Most dietary guidelines say this group is age 9 to 18, but since your bones are still building in your 20s, I put you here. 

Calcium: Unfortunately, kids and young adults in this group take in lower than recommended doses, with an average daily calcium intake of 100 mg. Aim for 1300 mg to 1500 mg per day of calcium and 600 IU of Vitamin D. In addition: 

  • Maximize how much you get in your diet; most children will need a supplement to have sufficient calcium. If you’re not sure, check with your pediatrician. 
  • Don’t forget the impact of exercise! In one study of people age 13 to 27, doing regular weight-bearing exercise and maintaining a normal body weight were the most important factors for maximizing bone mass. 
  • Avoid excessive caffeine and carbonated beverages as they may contribute to poorer bone mass. 

Vitamin D: The National Academy of Medicine and American Academy of Pediatrics recommend intake of 600 IU per day. Most children and adolescents won’t get their recommended dose of vitamin D through diet alone, so supplementation may play an important role. 

Adults over the age of 30 without osteoporosis 
This is the tougher area. There is no evidence that calcium supplementation is beneficial for healthy adults who do not have osteoporosis or osteopenia. In addition, the risks of heart disease and kidney stones may outweigh the benefits. As a result, the United States Preventive Services Task Force does not recommend taking calcium supplements if you’re in this age group. 

Calcium: Aim to get 1000 mg per day in your diet, and 1200 mg per day if you’re a man over 70 years old or a woman over 50. 

Vitamin D: Adults at risk for low vitamin D should either take a supplement or have their vitamin D levels checked. These include the elderly, anyone who has been hospitalized, people with kidney disease or intestinal disease or those with other chronic conditions. People who don’t get adequate sun exposure are also at risk. That includes most of us in the winter, especially if you live in the northern part of the country. 

The Office of Dietary Supplements also includes people with dark skin, the obese and those who have had gastric bypass surgery. Aim for a total of 600 IU of vitamin D daily (including diet plus supplements) and 800 IU per day if you’re over 70. 

Adults over the age of 30 with osteoporosis or osteopenia 
In this group, calcium supplementation has been shown to reduce the rate of bone loss, so supplementation is recommended. 

  • Women who have reached menopause: 1200 mg per day of calcium; 600 IU per day of vitamin D for women under age 70, and 800 IU per day for women 70 and older. 
  • Men and premenopausal women: The jury’s still out on this, but many experts believe that 1000 mg to 1200 mg per day of calcium and 600 IU of vitamin D is beneficial. For men 70 and older, 800 IU of vitamin D is recommended. 

Bottom line? When it comes to calcium and vitamin D, stick to the daily recommended intake for your age and health status, and always talk with your healthcare provider if you have questions. 

Medically reviewed in June 2019. Updated in March 2021. 

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