Effects of Weight Control during the Menopausal Transition on Bone Mineral Density
Park et al, 2007, J Clin Endocrinol & Metb, vol 92, No. 10 3809-3815
Univ of Inje, Seoul Korea, Univ of Georgia, USA, & Univ of Pittsburgh, USA

Background
Studies of weight loss & changes in bone mineral density (BMD) have primarily been short-term trials in obese subjects.

Objective
The authors examined the effects of a 5-year intervention designed to prevent menopausal weight gain or promote modest weight loss on BMD in pre-menopausal women participating in the Women’s Healthy Lifestyle Project.

Design
This study enrolled 373 pre-menopausal women (aged 44-50 yr) and randomly assigned them to either lifestyle intervention (175 women, low-fat dietary modification, weight loss, and physical activity intervention) or control group (198 women). BMD and body weight were measured at baseline, annual follow-up visits (18, 30, 42, & 54 months), and two post-intervention follow-ups (66 & 78 months). BMD was measured by dual x-ray absorptiometry.

Results
Over the 54 months of intervention, women in the intervention group lost 0.4kg, whereas control women gained 2.6kg. The intervention group experienced significantly greater hip bone loss ( -0.20%/yr ) than the control group ( -0.03%/yr ).

When considering both menopausal status & use of hormone therapy (HT), the annualized BMD changes were lower in women reporting HT use; nevertheless, among women on HT, those who lost more than 3% body weight experienced greater total hip BMD loss ( -0.25%/yr ) compared with those who gained weight ( -0.02%/yr ).

Conclusion
Women randomized to a lifestyle intervention aimed at preventing menopausal weight gain or promoting modest weight loss experienced greater rates of hip bone loss than control women.

(Editor: Women who go on weight reducing strategies must remember that losing too much weight may adversely affect their bone mass, and make them lose bone into their older years, predisposing them to osteoporosis. So, do be careful ! )