Nutrition is foundational for all aspects of wellness, especially bone health. Your diet can set the stage by providing the foundational nutrients needed for strong bones. On the other hand, a diet lacking these nutrients can increase your risk of developing osteoporosis and other bone problems later in life.
Bone health requires a multi-faceted approach, and diet is only one part. Lifestyle habits such as incorporating weight-bearing exercise, not smoking, and minimizing alcohol matter, too. But understanding what foods contribute to healthy bones is an essential piece of a holistic plan to keep your bones strong.
Let's examine the most important micronutrients for bone strength and the best food sources for each.
Foods and Bone Strength
Strong bones require both macronutrients and micronutrients. Macronutrients are those nutrients we need in large amounts, such as carbohydrates, proteins, and fats. Micronutrients are those required in much smaller quantities and include vitamins and minerals.
Micronutrients are critical for supporting bone health because your bone structure is literally made from these vitamins and minerals. Bone strength is measured by bone dens or how much mineral is packed into your bone tissue (Medline Plus, 2015). The denser your bones are, the stronger they are, so you want to make sure you get enough bone-building nutrients to promote bone growth and formation.
All of the following micronutrients work together to support your bone health:
- Calcium. Calcium is the most abundant mineral in our bodies. It's usually the focus of health messages about bone health—although you need all the other nutrients to make sure calcium can do its job (NIH Osteoporosis and Related Bone Diseases, 2018). About 99% of the calcium in our bodies is stored in our bones and teeth.
But calcium has other jobs in your body aside from building bones, so if you don't eat enough calcium-containing foods, calcium is taken from your bones to make sure blood levels are stable.
Adults 19-50 years old need about 1,000 mg of calcium, and women over 50 need 1,200 mg of calcium per day (NIH, 2022).
- Vitamin D. A fat soluble vitamin (meaning your body will store any excess instead of removing it from your body via urine), vitamin D helps shuttle calcium into your bones. Without enough vitamin D, bones can become weak. Even if you get enough calcium, you can't absorb enough to support new bone formation without vitamin D (Christakos, 2011).
Adults need daily intakes of 600 IU of vitamin D up to age 70 and 800 IU after age 70 (NIH, 2022).
- Vitamin K. Vitamin K is also a fat-soluble vitamin found in food, but it's also synthesized by your gut bacteria. There are two main groups of vitamin K, and both appear to play a role in bone health (although K2 may be the most biologically active) (Fusaro, 2017).
Vitamin K helps maintain bone density by directing calcium to the bones rather than allowing it to accumulate in arteries and soft tissues where it can cause problems. Low vitamin K is linked to an increased risk of fractures and bone loss (Has, 2017).
Adult women need about 90 micrograms of vitamin K per day (NIH, 2021).
- Magnesium. Magnesium is a mineral involved in over 300 biochemical reactions in the body, including those that help maintain normal muscle and nerve function, a healthy immune system, and strong bones.
About 60 percent of the magnesium in your body is found in the bones (Castiglioni, 2013). It's needed for calcium absorption and metabolism, and it's also required to convert vitamin D into its active form—illustrating why you can't just focus on one nutrient for bone health.
Adult women under 30 need 310 mg and women over 30 need 320 mg of magnesium per day (NIH, 2022).
- Potassium. Potassium contributes to strong bones by helping to regulate calcium balance in the body by reducing how much you excrete from the body. Studies show that diets higher in potassium, especially from fruits and veggies, are linked to a lower risk of osteoporosis (Ha, 2020).
Adult women need 2600 mg of potassium per day (NIH, 2022).
What is the Ideal Diet for Bone Strength?
There's no one perfect way to eat for bone health because we all have different dietary preferences and needs. You are unique, so your nutritional needs can vary based on age, gender, nutrition status, activity level, and more. But overall, food provides the foundation for a bone-supportive diet.
Sometimes supplements are needed to fill in the blanks, especially if you have specific dietary restrictions that limit the variety of foods you can eat.
Dairy products are the primary source of calcium for many people. Milk, cheese, and yogurt provide calcium and other nutrients like vitamin D, potassium, and phosphorus.
Fish with edible bones, such as sardines and salmon, also contain calcium.
But if you prefer not to eat fish or dairy, you have plenty of options, including:
- Dark leafy green vegetables like collard greens, kale, turnip greens, or spinach
- Soybeans, tofu, edamame
- Calcium-fortified foods like cereal, almond milk, and orange juice
- Nettle and oatstraw tea
Whether or not you add a calcium supplement depends on how much calcium you're getting from food. Your doctor or a Registered Dietitian Nutritionist (RDN) can help you decide if you need to supplement.
Vitamin D-Rich Foods
The primary way to get vitamin D is from the sun. Your skin converts UV rays into vitamin D, but sunscreen or sun protective clothing limits absorption. Other factors like age, skin pigmentation, and time of year can also affect how much vitamin D you make. It's estimated that nearly 20 percent of people over the age of one don't get enough vitamin D (Herreck, 2019).
Foods like fatty fish (salmon or sardines), egg yolks, liver, mushrooms, and cheese have small amounts of vitamin D (NIH, 2022). There are also fortified options (meaning vitamin D is added to the product) like milk, almond milk, orange juice, cereals, and bread, but sometimes supplementation is necessary to get enough or during times of the year with less sunlight.
Vitamin K-Rich Foods
Vitamin K1 is found primarily in green leafy vegetables, while vitamin K2 is found in fermented products.
Good sources of vitamin K include:
- Leafy greens like kale, spinach, and collard greens
- Brussels sprouts
- Fermented foods like sauerkraut, miso, kim chi, or kefir
- Natto, a pungent, fermented soybean product found in Japanese markets or online
- Aged cheese
Magnesium is found in various plant-based foods, especially whole grains, leafy greens, legumes, nuts, and seeds. Top sources of magnesium include:
- Pumpkin seeds
- Chia seeds
- Swiss chard
- Black beans
It's easy to get enough potassium with a diet rich in whole foods because it's found in many different fruits, vegetables, and legumes. Good sources of potassium include:
- Dried fruit
How to Include More Bone-Strengthening Foods in Your Diet
- Add yogurt to your breakfast cereal or oatmeal.
- Enjoy a salad made with leafy greens and topped with seeds, hard-boiled eggs, or grilled chicken for lunch.
- Make black bean quinoa tacos for dinner.
- Snack on nuts and dried fruit.
- Experiment with tofu by adding it to stir-fries or using it as a meat alternative in recipes
The best bone-strengthening diet includes a variety of nutrient-rich foods that work together to ensure you're getting all the nutrients you need.
If you need more individualized support or are concerned about your nutrient intake, an RDN can help you learn more about which foods (or supplements as needed) are best for you.