Archive | Obesity RSS feed for this section

Noninvasive Brain Stimulation for Food Cravings

8 Aug

A paper in the journal Psychosomatic Medicine reviews the research on Brain Stimulation as a treatment for food cravings. The findings suggest that repetitive transcranial magnetic stimulation might be helpful. On the other hand, transcranial direct current stimulation did not seem to have a significant effect.

Here is a video on TMS:

Here is the abstract:

Objective: The primary aim of this review was to evaluate the effectiveness of noninvasive brain stimulation to the dorsolateral prefrontal cortex (dlPFC) for modulating appetitive food cravings and consumption in laboratory (via meta-analysis) and therapeutic (via systematic review) contexts.

Methods: Keyword searches of electronic databases (PubMed, Scopus, Web of Science, PsychoInfo, and EMBASE) and searches of previous quantitative reviews were used to identify studies (experimental [single-session] or randomized trials [multi-session]) that examined the effects of neuromodulation to the dlPFC on food cravings (n = 9) and/or consumption (n = 7). Random-effects models were employed to estimate the overall and method-specific (repetitive transcranial magnetic stimulation [rTMS] and transcranial direct current stimulation [tDCS]) effect sizes. Age and body mass index were examined as potential moderators. Two studies involving multisession therapeutic stimulation were considered in a separate systematic review.

Results: Findings revealed a moderate-sized effect of modulation on cravings across studies (g, -0.516; p = .037); this effect was subject to significant heterogeneity (Q, 33.086; p < .001). Although no statistically significant moderators were identified, the stimulation effect on cravings was statistically significant for rTMS (g, -0.834; p = .008) but not tDCS (g, -0.252; p = .37). There was not sufficient evidence to support a causal effect of neuromodulation and consumption in experimental studies; therapeutic studies reported mixed findings.

Conclusions: Stimulation of the dlPFC modulates cravings for appetitive foods in single-session laboratory paradigms; when estimated separately, the effect size is only significant for rTMS protocols. Effects on consumption in laboratory contexts were not reliable across studies, but this may reflect methodological variability in delivery of stimulation and assessment of eating behavior. Additional single- and multi-session studies assessing eating behavior outcomes are needed.

Weight loss improves memory in type II diabetes

25 May

A thesis from Umeå University titled “Brain function and glucocorticoids in obesity and type 2 diabetes including effects of lifestyle interventions.”  From the conclusion:

” Cortisol levels are linked to prefrontal brain structure and, at least in type 2 diabetes, lower memory performance. Furthermore, the dysregulated GC metabolism in obesity can be reversed by long-term diet- induced weight loss. Finally, dietary interventions with associated metabolic improvements alter functional brain responses during memory testing, including increased activation of the hippocampus. Whether these changes are linked to alterations in GC exposure and mediate improved cognition requires further study. “

More on the obesity dementia link

25 Jun

Why is obesity linked to dementia? One possibility is that obesity causes type II diabetes, which, in turn is a risk factor for dementia. Dr. Mirkrin does a good job of explaining this hypothesis.

This suggests that the things, like exercise and a plant based diet, that reduce the risk of  type II diabetes also reduces the risk of dementia.

Obesity and dementia

20 Jun

A study published in the March issue of the journal Obesity suggests that current projections may underestimate the prevalence of dementia in the future.

It is well know that the number of cases of dementia will increase as result of the aging of the baby boom generation. However,  these forecasts have not factored in the fact that many people now in middle age are obese and, thus, are at a higher risk for dementia.

The authors of the study project that in the United States the rate of dementia will be 9% higher than current estimates In China they project the rate will be 19% higher. They call for policies that will help reduce midlife obesity.

%d bloggers like this: