Background: Influences of dietary patterns on musculoskeletal health are poorly understood in middle-aged women. This study aimed to examine associations between dietary patterns and bone mass, muscle strength and balance in middle-aged women.
Methods: Cross-sectional analysis in 347 women aged 36-57 years. Outcomes: total body BMC and femoral neck and lumbar spine BMD (DXA), lower limb muscle strength (LMS), and dynamic and static balance (timed up and go (TUG), step test (ST), functional reach test (FRT) and lateral reach test (LRT)). Diet was assessed by the Cancer Council of Victoria food frequency questionnaire and dietary patterns identified by exploratory factor analysis. Scores for each pattern were calculated from the intake of each food group weighted by its factor loading. Associations were assessed using multivariable linear regression.
Results: Three dietary patterns were identified: ‘Healthy’ (high consumption of vegetables, legumes, fruit, tomatoes, nuts, snacks, garlic, whole grains and low intake of high-fat dairy), ‘high protein-high fat’ (high intake of red meats, poultry, processed meats, potatoes, cruciferous and dark-yellow vegetables, fish, chips, spirits and high-fat dairy) and ‘Western’ (high intakes of meat pies, hamburgers, beer, sweets, fruit juice, processed meats, snacks, spirits, pizza and low intake of cruciferous vegetables). Mean pattern scores (range) were 194 (-84-703), 147 (21-834) and 58 (-16-536) for healthy, high protein-high fat and Western patterns respectively. In adjusted analyses, healthy pattern score was positively associated with LMS (β = 3.9 (95% CI 1.2, 6.6) kg/SD of score) and Western pattern score was negatively associated with FRT ((β = -0.66 (95% CI -1.30, -0.02) cm/SD of score). There were no other associations between any dietary pattern and any other outcome.
Conclusion: Dietary patterns do not appear to impact bone mineral density in middle-aged women but maintaining a healthy diet may be important for lower limb muscle strength and possibly balance.