Expert: What to Eat (and Not Eat) to Build Stronger Bones  

Your age, sex and genetics all contribute to your bone strength and density. Your diet is another factor and one that you can control.

We’ve all heard that calcium, when combined with vitamin D  to aid absorption, helps support strong bones. Calcium also plays a key role in blood clotting, muscle contraction and nerve function, making it essential for overall health beyond bone strength. If you have low levels of calcium and/or vitamin D (a deficiency), you are at higher risk for low bone density. Osteopenia is the early stage of this condition; osteoporosis is more advanced and can increase your risk of bone fractures. 

How much calcium do you need?

According to the U.S. National Institutes of Health, recommended daily allowances of calcium are based on your age and sex, with special recommendations for pregnant and lactating people.

Are supplements enough? 

You may be tempted to just take a daily calcium supplement and call it a day. But the best way to ensure your body is getting enough of this essential mineral (plus vitamin D for absorption) is to regularly eat and drink calcium- and vitamin D-rich foods. The research on supplement absorption and effectiveness is not as strong as the evidence supporting the health benefits of a nutrient-rich diet full of whole foods. Plus, dietary supplements are not tested by the U.S. Food and Drug Administration, so product quality, purity, strength and safety varies and is difficult to confirm.

“While food sources of calcium are generally preferred, some individuals — such as those with limited dairy intake, lactose intolerance, or certain medical conditions — may still require supplementation to meet their needs,” says Paula Domingues, M.S., RDN, LDN, a clinical dietitian with the University of Miami Health System.

Taking too high a dosage of calcium supplements, especially without food, may contribute to the development of calcium stones, the most common type of kidney stones. Research studies on this vary in their conclusions. As a precaution, if you have previously had kidney stones, speak with your primary care physician or a urologist before taking a calcium supplement.

Some research has found that calcium supplements can contribute to the buildup of calcium in the arteries, which increases the risk for cardiovascular disease, especially in postmenopausal women.

Who might benefit from calcium plus vitamin D supplements?

• adults who cannot or do not get enough calcium from diet alone
• adults who’ve had bariatric surgery and, as a result, cannot fully absorb calcium
• adults with gastrointestinal conditions that cause poor calcium absorption (such as celiac disease)

Beyond Milk: Calcium in Your Diet

Dairy products are undoubtably a great source of calcium. They include dairy milk, cheese, and yogurt. Keep in mind that these foods can also contain a lot of saturated fat, which can raise your cholesterol and contribute to obesity and cardiovascular disease.

Dairy yogurt has a reputation for being a healthy option, but many varieties include added sugars. In excess, added sugars can lead to weight gain, blood sugar spikes and crashes, and elevated A1C levels (which can indicate pre-diabetes and diabetes). These days, it’s not hard to find delicious low-fat and nonfat yogurt products without added sugars, including plain Greek yogurt, which is also a great source of protein.

You may be surprised that many plant-based foods are good sources of calcium. Plus, plant-based diets make it easier to limit your intake of saturated fats, cholesterol and added sugars. You don’t need to be vegetarian or vegan to benefit from eating more whole fruits, vegetables, beans and lentils, seeds and nuts.

Enjoy these plant-based, calcium-rich foods for bone health:

• kale
• bok choy
• turnip, collard, beet and mustard greens
• broccoli 
• almonds  
• calcium-fortified almond and rice milks (unsweetened)
• sesame seeds and tahini
• tofu
• calcium-fortified orange juice 

“While plant-based sources like spinach and beans contain calcium, some also contain oxalates or phytates, which can reduce calcium absorption,” Domingues says. “Choosing low-oxalate greens, such as kale, bok choy, collard greens, and arugula, can help optimize your calcium intake from plant sources.”

How to get enough Vitamin D 

To absorb and use calcium, your body also needs enough vitamin D. Getting some sun exposure helps your body produce this vitamin. But, too much time in the sun puts you at risk for skin cancer and skin damage. Plus, enjoying a little sunshine each day isn’t always possible.

“While your body can store vitamin D in fat tissue and the liver, it must be converted into its active form for calcium absorption,” Domingues says. “Since this process is tightly regulated, regular vitamin D intake remains important.”

To ensure that you get enough of this essential vitamin, eat at least some of the following vitamin D sources for bone strength at least twice a week: 

• wild caught salmon 
• tuna 
• trout 
• herring 
• sardines  
• egg yolks 
• mushrooms  
• yogurt (unsweetened)
• vitamin D-fortified foods
• cod liver oil

Be aware that some of these foods are high in sodium, which can elevate blood pressure and contribute to congestive heart failure and kidney disease. If you have high blood pressure, avoid eating a lot of high-sodium foods, and consider taking a vitamin D supplement.

Is your body absorbing enough calcium?

The following foods, drinks and medications can lower or block your body’s calcium absorption:

• plant compounds (like oxalic acid): found in spinach, beans and sweet potatoes
• medications that may reduce blood calcium levels: bisphosphonates, some antibiotics, chemotherapy, calcitonin and proton pump inhibitors
• caffeine
• alcohol, which can interfere with pancreas and liver function needed to enable the body to activate and absorb calcium
• excessively salty foods, which can leach calcium from the body

You don’t need to completely avoid these things, but consume these foods and beverages in moderation. If you need to take a prescription or over-the-counter medicine that may interfere with your calcium absorption, speak with your doctor. They may recommend a different medication, dosage, or timing; a calcium supplement; or a blood test to confirm if you’re calcium deficient.

Do you have a calcium deficiency?

Your doctor can order a serum calcium blood test to determine if your calcium level is considered normal for your age and sex and sufficient to support your bone strength. Depending on the results, you may need additional tests to evaluate your vitamin D, parathyroid hormone and ionized calcium levels. 

If you are at risk for osteopenia or osteoporosis, a DEXA scan can measure your bone density.

What else does your body need for strong bones?

The electrolyte phosphorus (phosphate) is crucial for bone growth and mineralization. Many heart healthy foods like chicken, whole grains, beans and lentils, seafood, nuts and seeds are good sources of phosphate. Sodas can be particularly high in this mineral.

While the body needs phosphorus for bone health, having the right balance of it is essential.

Phosphorus deficiency can lead to bone-softening conditions like rickets and osteomalacia. But, having excess phosphate in the blood is called hyperphosphatemia, a condition that can actually remove calcium from bones, making them brittle. People with advanced chronic kidney disease or kidney failure are more likely to develop hyperphosphatemia. Consuming too much phosphate in your diet can also lead to this condition.

“Phosphorus competes with calcium for absorption in the gut, and excessive intake — especially from processed foods and sodas — can contribute to calcium loss,” says Domingues. “Maintaining a healthy calcium-to-phosphorus ratio is essential for bone health, particularly in individuals with kidney disease.”

In addition to dietary recommendations, weight training and resistance exercise is proven to strengthen bones and help prevent falls and fractures. This becomes more relevant as you age and naturally lose muscle mass.

Dana Kantrowitz is a contributing writer for UHealth’s news service.

Last reviewed in April 2025 by Paula Domingues, M.S., RDN, LDN, a clinical dietitian with the University of Miami Health System.

Originally published on: July 08, 2022

Tags: bone strength, calcium, calcium plus vitamin D, calcium supplements, Nutrition, osteoporosis prevention, Paula Domingues