What food immediately comes to mind when you think of build strong bones? Milk, naturally. Mom probably poured you a glass with every meal when you were a kid to help you grow. But you may feel that milk isn’t doing your body as good in your older age if you’re one of the 36 percent of Americans who has lactose malabsorption and may experience diarrhea, gas, and bloating after drinking dairy. While there are obvious ways to get around these common side effects, such as: lactose-free dairy products—let’s spill the milk and watch a lesser-known source of calcium that gives you even more of this bone-building mineral than cow’s milk: sardines.
A serving of 3 ounces sardines contains about 325 milligrams (mg) of calcium compared to about 276 mg and 299 mg for whole milk and skimmed milk, respectively, according to the National Osteoporosis Foundation and the National Institutes of Health. That’s about a third of the recommended daily intake (RDA) of 1,000 mg for most adults. The RDA for women over 50 and men over 70 is 1,200 mg.
Break down bones
Calcium is an essential mineral for your body. It plays a role in proper muscle function, blood clotting, hormone secretion and contraction and widening of blood vessels and, in particular, calcium is a large part of the structure of your bones, according to The Journal of Clinical Endocrinology and Metabolism.
Your bones are not set in stone, so to speak; they are constantly breaking down and rebuilding, unbeknownst to you.
Unless you keep supplying your body with calcium from the food you eat and by taxing your bones with exercise, your body can make less bone or lose bone and weaken with age. This is known as the bone disease osteoporosis, a reduction in bone density that often leads to fractures. To learn more about this debilitating disease, read: The #1 cause of osteoporosis, according to science.
Eating sardines builds bone strength because you eat the whole fish, including the soft bones, the source of the all-important calcium. Some researchers have noted that Japan has less osteoporosis than the United States, although the Japanese consume far less dairy than Americans due to the high consumption of fish in Japan and other Asian countries.
Other nutrients in fish, such as vitamin D and protein, also play a role in building bones. Vitamin D is essential for calcium absorption and bone mineralization, which makes for denser, stronger bones. Fatty fish such as sardines are among the best dietary sources of vitamin D3, which is believed to be the more effective of the two types of vitamin D for bone health, according to a 2010 report in the journal nutrients. (Read more: The #1 Best Vitamin D Supplement to Take, Dietitian Says.) A can of sardines provides just over 40% of your daily vitamin D requirement, according to the USDA.
Protein, a plus
Sardines, like milk for building bones, also provide a healthy dose of muscle-building protein, 25 grams per 3-ounce serving of fish. That’s nearly half the amount of protein a 50-year-old sedentary woman weighing 140 pounds needs per day, according to the Harvard health blog.
Clinical studies have demonstrated the importance of proteins in protecting against osteoporosis. After all, proteins make up about a third of your bone mass.
A large study based on clinical trials and observational studies from the Women’s Health Initiative followed more than 144,000 postmenopausal women over a six-year period. The researchers, who report in the American Journal of Clinical Nutrition found that higher protein consumption was associated with significantly higher bone density in the hip, spine and whole body and also a lower risk of forearm fractures in the women.
There are other good reasons to get some of your calcium from sardines. First, in addition to calcium, vitamin D, and protein, you’ll be consuming more heart-healthy omega-3 fatty acids, which are found in abundance in fatty fish like sardines.
A study from 2021 in Clinical Nutrition points to another plus: diabetes prevention. In a study of older adults with prediabetes, researchers found that just two servings of sardines per week for 12 months provided enough calcium, vitamin D and omega-3 fatty acids to significantly reduce the risk of type 2 diabetes. Of the group of people who included sardines in their diet, 37% had a high risk of developing diabetes at the start of the study. By the end of the trial, only 8% remained at very high risk.
Tip: While you’re at the grocery store stocking up on canned sardines, fill your cart with these 20 Best Calcium Rich Foods That Are Not Dairy.
For more news on healthy eating, make sure you Sign up for our newsletter!
Read this next: