There is an ongoing and worsening problem with obesity in the developed, and much of the developing world. Although it has long been realized that Western diets that are rich in sugar and fat play an important role in this, it has only recently been realized that exposure to these diets, particularly in childhood, can damage the part of the brain that determines how much fat there is in the body. The result of this damage is that the so-called "set-point" for fat in this part of the brain is pushed upwards. There is a lot of evidence from animals that activating the brain's balance (vestibular) system pushes this set-point for fat downwards to cause fat loss, probably because this tricks the brain into thinking that the animal is more physically active. The aim of this study is to see whether the same effect can be triggered in humans by non-invasively stimulating the vestibular system with a small electrical current through the skin behind their ears.
There is a growing realization that obesity can, in many ways, be viewed as a neurological disease triggered by lifestyle factors. There is clear evidence that the arcuate nucleus in the hypothalamus regulates a "set-point" for how much fat the body should have. It does so by altering appetite and metabolic rate so that deviations too far in either direction are strongly resisted. This set-point is determined by genetic, epigenetic and lifestyle factors. Thus, excessive exposure to dietary monosaccharides, such as glucose, and saturated fats, especially in childhood and adolescence, can damage the neurons of the arcuate nucleus and push the set-point up. This then can condemn sufferers to a lifetime of obesity. Establishing a method of tuning down the set-point for body fat thus has to be a goal if we are to successfully combat the current obesity pandemic. A significant amount of animal work suggests that stimulating the vestibular system in the inner ear, by means of chronic centrifugation, actually does just that and causes a reduction in body fat. This is likely because the chronic vestibular activation is taken by the brain to represent a state of increased physical activity, and in order to optimize homeostasis it would be appropriate for the body to have a leaner physique, by reducing unnecessary energy expenditure from carrying excess fat. It is possible to stimulate the vestibular nerve in humans by applying a small electrical current to the skin behind the ears. This is an established technology that is believed to be safe, but only previously used for research purposes. We found in a pilot study that recurrent stimulation of this kind for two or three hours a week over four months led to a statistically significant reduction in truncal fat in the active group as opposed to the control group who underwent sham stimulation. Given the current, and increasing levels of global obesity, it is important to determine whether non-invasive electrical vestibular nerve stimulation (VeNS), otherwise known as galvanic vestibular stimulation, is a viable treatment option. Changes in body fat will be measured using dual energy X-ray absorptiometry (DEXA) scans.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
TREATMENT
Masking
QUADRUPLE
Enrollment
22
Battery powered headset that can be recharged when not being used.
Identical in external appearance to the vestibular nerve stimulation device, this device is also powered by a battery and needs to be periodically recharge when not being used. However it discharges into an internal resistor and does not stimulate the vestibular nerve.
Altman Clinical and Translation Research Institute, UC San Diego
San Diego, California, United States
Change in Mean Body Weight (kg)
Mean total body weight loss (TBWL) from the start of treatment (as a percentage of baseline total body weight). Change = 12 month score - baseline score
Time frame: Baseline and 12 months
Change in Categorical Body Weight
Change in Categorical Body Weight measured by BMI: Normal: 18.5-24.9 Overweight: 25.0-29.0 Obese: \>30.0 Average BMI calculated. Change = 12 month score - baseline score
Time frame: Baseline and 12 months
Visceral Adipose Tissue
The difference in mean percent loss of baseline visceral adipose tissue (in kilograms) in the vestibular stimulation versus sham stimulation group, as measured by means of a whole body DXA scan. Change = 12 month score - baseline score
Time frame: Baseline and 12 months
Lean Muscle
Change in total lean (muscle) mass in kilograms between vestibular stimulation and sham stimulation groups as assessed using whole body DXA scans.
Time frame: Baseline and 12 months
Change in Categorical Body Fat
The proportion of subjects who lose at least 5% of baseline total body fat in the active versus placebo treated groups. (As measured by a whole body DXA scan).
Time frame: Baseline and 12 months
Change in Mean Body Fat (g)
The difference in mean percent loss of baseline total body fat in the active versus placebo treated groups. (As measured by means of a whole body DXA scan). Change = 12 month score - baseline score
Time frame: 12 months
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.