Weighted Vests: Are They Effective for Weight Loss?

Medscape

4 days ago

With the ongoing obesity epidemic, researchers are constantly looking for strategies that optimize weight loss while minimizing associated side effects. One strategy currently gaining interest is the use of weighted vests— form-fitting garments into which weights are sewn or carried in pockets, enabling the wearer to add or remove them as needed. In theory, this offers a nonpharmacologic way to induce weight loss without the side effects of medications or weight-loss surgery, but with potential bone-sparing effects. The latter is important because even modest weight loss can reduce bone density and strength, increasing the risk for fracture.
Weight loss — particularly when induced by caloric restriction — is associated with bone loss, especially at the hip. This is a consequence of loss of muscle mass and an unloading of bones from the decrease in body weight. Even modest diet-induced weight loss results in small but significant reductions in hip bone mineral density (BMD), with less consistent changes at the spine or whole body. These skeletal losses may increase fracture risk, particularly in older adults, and are more pronounced when weight loss occurs in the absence of exercise. Resistance training or combined aerobic-resistance exercise mitigate but do not fully prevent this bone loss.
How Do Weighted Vests Help?
Weighted vests can be used to preserve muscle mass during periods of caloric restriction. This is achieved by increasing gravitational loading and placing mechanical stress on weight-bearing tissues. Local fat mass is theoretically reduced by the work required to wear the weighted vest. Preservation of muscle mass has the dual benefit of preserving bone mass and maintaining resting metabolic rate (RMR). This is important because weight loss typically results in a lower RMR, which makes subsequent weight loss more difficult.
Although using weighted vests does not lead to the same degree of weight loss reported with GLP-1 receptor agonists such as semaglutide, or GLP-1/glucose-dependent insulinotropic peptide (GIP) receptor agonists such as tirzepatide, the data demonstrate benefits of this strategy. For example, 5 weeks of high-load vest use (11% of body weight worn 8 hours per day) vs a low-load vest (1% of body weight) reduced fat mass and waist circumference with no significant change in overall body weight. Loss of fat mass and a reduction in waist circumference are not inconsequential outcomes. Fat distribution (particularly an excess of visceral fat with an increased waist circumference) is a major driver of many metabolic morbidities associated with obesity. In fact, newer definitions of preclinical and clinical obesity emphasize body fat distribution and waist circumference, rather than absolute body weight.
The impact of weighted vest use on skeletal health is inconclusive at this time. Snow and colleagues reported preservation of hip BMD over a 5-year period in older, postmenopausal women when weighted vest use was combined with jumping exercises. However, a randomized controlled study from Wake Forest University (INVEST in Obesity) involving 150 older adults with obesity did not find a bone-protective effect of weighted vest use or resistance training following intentional weight loss. Further studies are needed to evaluate the impact on BMD of varying durations of vest use and varying weights of the vest.
In conclusion, studies thus far have not demonstrated a significant impact of weighted vests for total weight reduction, although reductions in local fat mass and waist circumference may confer some metabolic benefit. These vests may provide mechanical stimuli that support musculoskeletal integrity; however, further research is necessary to prove this point and data available thus far are conflicting.