June/July 2022 Issue

Bone Health: What’s New in Osteoporosis Prevention
By Carrie Dennett, MPH, RDN, CD
Today’s Dietitian
Vol. 24, No. 5, P. 10

Start Early to Build and Protect Bone

The Bone Health & Osteoporosis Foundation, formerly the National Osteoporosis Foundation, estimates that 1 in 2 women and up to 1 in 4 men aged 50 and older will break a bone due to osteoporosis.1 Genetics, hormones, nutrition, and lifestyle all play a role in the development and progression of osteoporosis.2 But given the Bone Health & Osteoporosis Foundation estimates that about 54 million Americans have low bone mass, placing them at increased risk of osteoporosis, are dietitians reaching clients and patients early enough, and with the best information, to help them build and maintain
healthy bones?

Speaking at the Academy of Nutrition and Dietetics’ Food & Nutrition Conference & Expo™ in October 2021, Jackie Buell, PhD, RDN, CSSD, ATC, a clinical assistant professor at Ohio State University, said she’s seen many premenopausal female runners who have low bone mass in their wrists. That may seem surprising, given that declines in bone mass typically occur in the menopausal years. But this calls attention to the need to focus on bone health when patients are building it, not when they’re already losing it.

Buell called osteoporosis a “pediatric silent disease,” pointing to a 2016 position statement from the National Osteoporosis Foundation that emphasized the importance of peak bone mass development in childhood and adolescence, noting that diet and physical activity are the primary modifiable factors associated with bone health.2

Diet and Lifestyle Factors Affecting Bone Health

Calories and Protein
While specific micronutrients, notably calcium and vitamin D, are key for bone health, macronutrients—especially protein—and adequate calorie intake matter, too. When someone isn’t eating enough, the low energy availability can lead to osteoporosis directly, or indirectly through loss of menstrual periods.3-5

“Once calories get too low for our body, we lose our menstrual cycle,” Buell said. “As we lose our menstrual cycle, we’re losing estrogen, and we end up losing some bone mass—not in the best interest for our aging years.” In males, inadequate energy intake can impair the hypothalamic-pituitary-gonadal axis, leading to testosterone deficiency and then to loss of bone mass.6

Estrogen inhibits osteoclasts—cells that degrade bone—so when estrogen levels drop, bone mass suffers. “When we are without estrogen, whether it’s because you’re a young person running too much and not fueling enough, or whether it’s because you’re in menopause and you’re losing estrogen, we seem to speed up those osteoclasts, and osteoblasts [cells that synthesize bone] cannot keep up,” Buell said.

Once clients and patients are getting enough calories to build and protect bone, protein is the next focus, Buell said. She generally recommends 1.6 or 1.7 g of protein per kilogram of body weight for people who are physically active to support both muscle and bone, although these levels—which are much higher than the RDA of 0.8 g/kg—may be appropriate for many patients who aren’t particularly active. “Amino acids are important building blocks for bone,” she said. “I wish more of us would study protein intake for optimal health, not for staying out of deficiency.”

Buell said it was long thought that protein contributed to leaching of calcium from the bones. “Since then, there have been many studies on higher protein levels,” she said. “And in general, we think now that higher protein levels are associated with better bone health.”7,8

Dietary Patterns
While protein is important, so is dietary balance, and Buell said it’s important to look at the patient’s whole diet. She suggests a whole-food diet that’s fairly plant based—including adequate fruits and vegetables for potassium and other nutrients—with lean meats.

She said there’s some evidence suggesting that the Mediterranean diet may help protect bones and delay osteoporosis.9 A vegan diet can be healthful, but there could be concern for bones if it’s very high in fiber, Buell said. “A high-fiber diet has been associated with low lumbar spine bone density. It’s unclear whether that’s an effect of binding estrogens or whether that’s the result of not eating enough.”7,10,11

One benefit of diets that include abundant plant foods is that they’re anti-inflammatory, and that benefit extends to bones. “Osteoclasts get turned on by inflammation, and we don’t want that to happen,” Buell said. For that reason, she added, more than two units of alcohol per day—about one 5-oz glass of wine or one 12-oz bottle of 5% ABV (alcohol by volume) beer—probably isn’t good for bones, as excessive alcohol consumption can be inflammatory.

Getting enough calories and protein in the context of an anti-inflammatory diet are the big-picture priorities, but managing vitamin D and calcium intake is important, too. Buell said that because the body’s vitamin D levels can change throughout the year, many people may need to rely more on supplementation during the winter months. She cautioned that calcium intake has a clearly defined upper limit of safety—2,000 to 3,000 mg/day for children and adults, depending on life stage—so more overall intake isn’t always better. When using calcium supplements, absorption is best with doses of 500 mg or less at one time.12 Buell said getting calcium from dairy products or fortified plant milks is ideal because it naturally spreads intake throughout the day: “Even if you could cut down to taking one calcium pill a day and get the rest of it from your diet, [that] would be a nice in-between.”

Buell also pointed to research suggesting that supplementation with synthetic vitamin K2, the form of vitamin K typically synthesized in the gut, in contrast with vitamin K1—phylloquinone—which we get from food, may help prevent fractures in postmenopausal women with osteoporosis.13

Body Weight and Muscle Mass
What about the role of body weight in bone health—does carrying more weight in daily life put more positive strain on the bones? Maybe yes, maybe no. “We know that individuals who are thin with a small frame have a higher risk of osteoporosis,” Buell said. “Is it really the total body weight, or is it the lean mass? I see an awful lot of fairly thin people who have next to no lean mass in the lab.”

Buell said she’s had success persuading patients with low lean mass to eat more calories to support muscle gains. “Most people don’t want to gain weight. But when they realize I’m trying to get them to gain more muscle, and that it’s going to help their bones—as well as their balance, as well as their sport—sometimes they’re willing to go there,” she said. “Don’t worry as much about what the scale says; worry more about muscle mass.”

She said it’s unclear based on current research whether fat mass affects bones and that it may be a matter of where on the body fat is located. “We think we know that visceral adipose tissue has more inflammatory cytokines related to it, and that might not be good for bone mass.”14

Exercise and Bone Health
Diet alone isn’t enough to build and maintain bone and muscle—physical activity is important, too. Bone responds to the stress the body puts on it, and adequate stress promotes bone modeling.15 However, bones can experience too much stress when, for example, athletes or recreational exercisers overtrain.

In 2004, the American College of Sports Medicine put out a position statement on physical activity and bone health that cautioned against running and jumping for people who already have bone issues, although newer research is somewhat debunking this.16-18 “Their recommendations were [for] ‘weight-bearing’ activity, with no guidance as to what does that weight bearing need to be,” Buell said. “Is all weight-bearing exercise the same? It probably is not.” The bone-building potential of physical activity is related to ground reaction forces, a noninvasive surrogate measure of bone strain.17 For example, Buell said, swimming and biking aren’t weight bearing. On the other hand, “walking’s weight bearing, but it’s probably not doing a lot for our bones,” she said.

Buell cited research by Belinda Beck, PhD, a professor of exercise science at Griffith University in Queensland, Australia, demonstrating that the best bone-building activity is high impact, fast, and with a heavy load.17,18 “You want to do more than two times your body weight, something that’s progressive, something that’s novel, and making sure that you’re getting some different motion in there,” Buell said.

The bottom line, according to Buell: “It’s never too late to start; younger is better. We know that younger people, when they do these kinds of activities, build their bone density through time better, because it helps them achieve that peak bone mass that we’re always talking about.”

— Carrie Dennett, MPH, RDN, CD, is the nutrition columnist for The Seattle Times, owner of Nutrition by Carrie, and author of Healthy for Your Life: A Holistic Guide to Optimal Wellness.

1. What is osteoporosis and what causes it? Bone Health & Osteoporosis Foundation website. https://www.bonehealthandosteoporosis.org/patients/what-is-osteoporosis/

2. Weaver CM, Gordon CM, Janz KF, et al. The National Osteoporosis Foundation's position statement on peak bone mass development and lifestyle factors: a systematic review and implementation recommendations. Osteoporos Int. 2016;27(4):1281-1386.

3. Mountjoy M, Sundgot-Borgen J, Burke L, et al. The IOC consensus statement: beyond the female athlete triad—relative energy deficiency in sport (RED-S). Br J Sports Med. 2014;48(7):491-497.

4. Elliott-Sale KJ, Tenforde AS, Parziale AL, Holtzman B, Ackerman KE. Endocrine effects of relative energy deficiency in sport. Int J Sport Nutr Exerc Metab. 2018;28(4):335-349.

5. Slater J, McLay-Cooke R, Brown R, Black K. Female recreational exercisers at risk for low energy availability. Int J Sport Nutr Exerc Metab. 2016;26(5):421-427.

6. Nattiv A, De Souza MJ, Koltun KJ, et al. The male athlete triad—a consensus statement from the Female and Male Athlete Triad Coalition part 1: definition and scientific basis. Clin J Sport Med. 2021;31(4):335-348.

7. Shams-White MM, Chung M, Du M, et al. Dietary protein and bone health: a systematic review and meta-analysis from the National Osteoporosis Foundation. Am J Clin Nutr. 2017;105(6):1528-1543.

8. Iguacel I, Miguel-Berges ML, Gómez-Bruton A, Moreno LA, Julián C. Veganism, vegetarianism, bone mineral density, and fracture risk: a systematic review and meta-analysis. Nutr Rev. 2019;77(1):1-18.

9. Cano A, Marshall S, Zolfaroli I, et al. The Mediterranean diet and menopausal health: an EMAS position statement. Maturitas. 2020;139:90-97.

10. Craig WJ, Mangels AR, Fresán U, et al. The safe and effective use of plant-based diets with guidelines for health professionals. Nutrients. 2021;13(11):4144.

11. Barron E, Cano Sokoloff N, Maffazioli GDN, et al. Diets high in fiber and vegetable protein are associated with low lumbar bone mineral density in young athletes with oligoamenorrhea. J Acad Nutr Diet. 2016;116(3):481-489.

12. Calcium: fact sheet for health professionals. National Institutes of Health, Office of Dietary Supplements website. https://ods.od.nih.gov/factsheets/Calcium-HealthProfessional/. Updated November 17, 2021.

13. Iwamoto J. Vitamin K2 therapy for postmenopausal osteoporosis. Nutrients. 2014;6(5):1971-1980.

14. Gkastaris K, Goulis DG, Potoupnis M, Anastasilakis AD, Kapetanos G. Obesity, osteoporosis and bone metabolism. J Musculoskelet Neuronal Interact. 2020;20(3):372-381.

15. Frost HM. A 2003 update of bone physiology and Wolff’s Law for clinicians. Angle Orthod. 2004;74(1):3-15.

16. Kohrt WM, Bloomfield SA, Little KD, Nelson ME, Yingling VR; American College of Sports Medicine. American College of Sports Medicine position stand: physical activity and bone health. Med Sci Sports Exerc. 2004;36(11):1985-1996.

17. Weeks BK, Beck BR. The BPAQ: a bone-specific physical activity assessment instrument. Osteoporos Int. 2008;19(11):1567-1577.

18. Beck BR, Daly RM, Singh MAF, Taaffe DR. Exercise and Sports Science Australia (ESSA) position statement on exercise prescription for the prevention and management of osteoporosis. J Sci Med Sport. 2017;20(5):438-445.