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"Medical Journeys" is a set of clinical resources reviewed by physicians, meant for the medical team as well as the patients they serve. Each episode of this journey through a disease state contains both a physician guide and a downloadable/printable patient resource. "Medical Journeys" chart a path each step of the way for physicians and patients and provide continual resources and support, as the caregiver team navigates the course of a disease.

Diet and related lifestyle issues have long been acknowledged as significant to prevention and treatment of osteoporosis.

"Nutrition is an area definitely not to be ignored, both in those with a previous fragility fracture and those diagnosed with osteoporosis or are at risk for it. In fact, diet is critically important for all people over age 50," said Douglas R. Dirschl, MD, chair of the Department of Orthopedic Surgery at Baylor College of Medicine in Houston. "Osteoporosis is just the tip of a very large iceberg, and for a subset of people the risk is already long in place."

While diet is important for maintaining bone and other aspects of health, can it make a large difference in bone mass in the presence of osteoporosis?

"Diet alone probably doesn't have as large an effect on bone mass as medications, but the DEXA [dual x-ray absorptiometry] number is only one part of the equation," Dirschl said. "Muscle mass, coordination, and flexibility have a huge effect on the fracture of osteoporosis patients." Diet has a large effect on muscles.

"Nutrition has a significant impact on bone health, particularly when combined with weight-bearing, muscle-strengthening, and balance-training exercises and prescribed medications," said Emma Laing, PhD, RDN, director of Dietetics at the University of Georgia in Athens and national spokesperson for the Academy of Nutrition and Dietetics. Ample calcium, vitamin D, protein, and a variety of fruits and vegetables are recommended for individuals at risk for or who are diagnosed with osteoporosis.

"A targeted nutrition intervention is unlikely to improve bone strength on its own; however, diet can improve the effectiveness of medications used to treat this condition," Laing added.

Calcium and Vitamin D

Bone is a mineralized connective tissue of which calcium is the major component, conferring bone strength and structure. The efficiency of calcium absorption is significantly enhanced by vitamin D, and in the presence of adequate amounts of this vitamin, intestinal .

Though these two key nutrients, especially calcium, are widely present in common foods, some osteoporosis patients may need daily supplements, especially of vitamin D, since this is harder to obtain in adequate amounts from diet alone. A consultation with a registered dietitian will assess a patient's vitamin D levels, dietary intake, and any supplemental needs.

Supplements

While a found that vitamin D supplementation alone did not prevent fractures in healthy adults, has shown that the combination of both vitamin D and calcium supplements is more likely to protect the skeleton.

"Patients at risk for fractures will probably benefit from calcium and/or vitamin D supplementation if they do not meet dietary intake requirements, have malabsorption syndromes, are taking medications that affect nutrient absorption, or if they are older and not regularly exposed to sunlight," Laing said.

Osteoporosis patients will typically need a multivitamin or supplement of calcium (as citrate, carbonate, gluconate, lactate, phosphate, or citrate malate) and/or vitamin D (as either vitamin D2 or D3) if they are unable to obtain sufficient amounts of these nutrients in the diet. The general recommendation for calcium intake is 1,000 mg/day for men ages 51-70 and 1,200 mg/day for women age ≥ 51 and men ≥ 71.

While some may be getting adequate calcium from diet alone, vitamin D is harder to obtain from food, "and in northern climates we don't get enough sun exposure for our bodies to manufacture vitamin D during the dark months," noted Joan Lappe, PhD, RN, of the College of Nursing Research and the Osteoporosis Research Center at Creighton University in Omaha, Nebraska. "In summer we wear sunscreen and protective clothing to avoid skin cancer."

Although recommendations from various organizations for vitamin D intake range from 600 to 1,000 IU a day for adults, Dirschl recommends 2,000 IU a day for all adults and especially for those with osteoporosis. A safe upper limit for vitamin D has been determined as 4,000 IU/day for most adults, and according to Lappe, an intake of 2,000 IU is advisable and an upper limit of 10,000 IU is considered safe.

Vitamin C

Laing said it is plausible that vitamin C plays a role in healing promotion after an osteoporotic fracture since it is involved in collagen synthesis, tissue healing, and bone formation. In addition, "reduced risks of fracture between individuals with high vs low consumption of vitamin C-rich foods have been reported."

While animal studies suggest a possible benefit in post-fracture bone regeneration, human data are lacking, she added, and no precise dose has been set for this purpose. Dirschl, however, said he recommends a daily intake of 1,000 mg of vitamin C, especially in patients recovering from fractures (the upper safe limit is set at 2,000 mg per day).

Vitamin K

This blood clotting–associated vitamin has recently been studied for its role in Vitamin K is available in two forms – K1 (phylloquinone) and K2 (menaquinone) -- and activates proteins involved in bone formation and mineralization. Vitamin K is also thought to foster the transition of osteoblasts to osteocytes and to limit the process of osteoclastogenesis.

"Consuming a diet high in vitamin K-rich foods has been linked to improved bone strength and reduced skeletal fractures -- likely mediated through the vitamin K-dependent protein osteocalcin, which is involved in bone turnover," Laing noted. So far, however, findings from studies examining the relationship between vitamin K and bone metabolism are conflicting and unclear.

Furthermore, vitamin K deficiency is rare, since vitamin K1 is abundant in green, leafy, and cruciferous vegetables as well as in vegetable oils such as canola and soy. Vitamin K2, predominantly produced by animal sources, is found in bacteria-treated foods such as aged cheeses, kefir, sauerkraut, and kimchi, as well as pork, poultry, liver, and eggs. Some meal-replacement shakes are fortified with vitamin K.

More recently researched than long-studied K1, vitamin K2 may have a more protective effect on bone than K1, but deficiencies of both types can have a negative effect.

An analysis of data from the large for example, found that women who consumed less than 109 mcg of vitamin K per day were more likely to break a hip. Some studies, many conducted in Japan, found that supplementation with vitamin K1 or K2 improved bone mineral density, and a few showed a decreased risk of bone fractures.

But evidence to support vitamin K supplementation is still too preliminary to make recommendations, and the FDA has not authorized a health claim.

Protein

While protein is essential for bone formation and fracture healing, "a surprising number of Americans are protein-deficient, even those who seem hale and are overweight," said Dirschl. "Protein malnutrition is common, and even in persons who carry a lot of fat, micro-testing shows they are deficient."

"The body needs protein to restore muscle mass and counteract the natural aging process of sarcopenia and repair fragility fractures," he added. "Recovering from a fracture is not a good time to choose a low-protein diet."

Laing said that dietary protein intakes that meet the (RDA) of 0.8 g/kg per day are likely beneficial for reducing fracture risk. "Protein targets that are slightly higher than the RDA -- for example, 1.0 to 1.2 g/kg per day -- have been suggested by some researchers as health-promoting for older, frail adults; however, intakes above the RDA do not consistently provide added benefit to the skeleton."

Items to Avoid

Items to avoid, to help reduce the risk of osteoporosis, include the following:

• Excess alcohol: Overindulgence in alcohol may interfere with bone growth and remodeling, resulting in decreased bone density and increased fracture risk. It is particularly harmful during adolescence when the body is attempting to reach the that will help stave off osteoporosis in later years. Alcohol may exert a negative effect directly or indirectly through the many cell types, hormones, and growth factors that regulate bone metabolism, and can also speed the excretion of calcium in the urine. "Excessive use of alcohol has been shown to disrupt calcium absorption and inhibit liver enzymes that help convert vitamin D to its active form," Laing explained. "If alcohol is consumed, adults should abide by the Dietary Guidelines for Americans recommendations of two drinks or less per day for men and one drink or less per day for women."

• High intake of sodium: Foods high in salt may increase calcium excretion and speed bone remodeling and loss. Therefore, osteoporosis patients should be advised to limit high-sodium foods such as canned, processed, and convenience foods and salty snacks -- and to use the salt shaker sparingly. Individuals with osteoporosis should read labels carefully and aim to keep sodium intake to no more than 2,300 mg per day, and at that , sodium should not have a significant impact on bone metabolism. "Maintaining sodium intakes below 2,300 mg per day is beneficial for several health-related outcomes, including the management and risk for hypertension and cardiovascular disease," said Laing. "It is therefore sensible for healthcare providers to encourage all patients to adhere to these recommendations."

• Excess caffeine: While the negative impact of caffeine on calcium absorption and retention is unclear -- especially in persons consuming a calcium-rich diet -- it's probably prudent for osteoporosis patients to consume caffeine in moderation by limiting intake of coffee, tea, and caffeinated colas.

• Excess phosphorus: Colas and other soft drinks and some processed foods may contain added phosphorus or phosphoric acid. While this mineral is an important component of bone, it may contribute to bone loss if consumed excessively. A buildup of phosphorus in the blood is associated with reduced calcium in the blood and the subsequent release of parathyroid hormone, which moves calcium out of the bones to correct the imbalance. "Though some studies show that caffeinated beverages and/or the phosphorus content of dark colas increase the excretion of calcium and promote osteoporosis development, findings from clinical studies are inconsistent," said Laing. "The harmful effects on bone from caffeine or colas could be more due to nutrient displacement, where soft drinks and caffeinated beverages are selected in lieu of calcium-containing foods and beverages." Lappe noted that some research has shown that calcium loss caused by these drinks can be counterbalanced by adequate calcium in the diet. A latte, for example, is a way to get caffeine but to simultaneously offset it with a dose of calcium. Laing disagreed, however, noting that a high-calcium diet is unlikely to offset the ill effects of caffeine, sodium, and alcohol on bone in the presence of other osteoporotic risk factors such as genetics, diabetes, and long-term glucocorticoid use. "In fact, a diet that is high in sodium and/or alcohol is often low in calcium and other bone nutrients by way of nutrient displacement," she said.

Read previous installments in this series:

Part 1: New Insights Into the Complex Biology of Osteoporosis

Part 2: The Latest on Osteoporosis Treatment and Diagnosis

Part 3: Osteoporotic Fragility Fractures

Part 4: Case Study: First-Time Mom's Severe Low Back Pain After Breastfeeding

Part 5: As Men Live Longer, Osteoporosis Looms Larger

Part 6: These Other Medical Conditions and Treatments Can Also Increase Osteoporosis Risk

Part 7: Talking to Patients About Osteoporosis

Part 8: Case Study: Shocking Development of Osteoporosis in a Teenager

Part 9: Osteoporosis and Oral Health

Part 10: Osteoporosis Patients Need Daily Physical Activity and 'Purposeful' Exercise