In this day and age of excessive calorie consumption, sedentary lifestyle and associated obesity, intermittent fasting, IF, seems like a much-needed solution. Stopping food intake for certain periods of time allows the digestive system, brain and other organs to take a break from metabolizing ingested calories. Continue reading “Intermittent Fasting and Weight Loss” →

“Eat food, not too much, mostly plants”, Michael Pollan’s seven words to healthy eating represents the most reasonable nutrition advice we can give to patients. Plant-based diet is the healthiest, safest and most environmentally friendly diet to consume. Numerous studies have demonstrated the benefits of vegetarian diets in terms of reducing the risk of cancer, hypertension, stroke, heart disease… Adding a small amount of animal protein to a plant-based diet prevents vitamin Continue reading “Is Keto Safe?” →

3 months after sleeve gastrectomy, a patient of mine lost 65 pounds and so did her husband on whom I did not operate. My patient was on a typical post gastric sleeve diet consuming 900 calories a day with excellent appetite control. Her husband was similarly enjoying great satiety while consuming a high fat diet amounting to at least 2500 calories a day. Continue reading “A Bariatric Surgeon Perspective on Keto Diet” →

Major food companies like Kraft Heinz, Nestle, Campbell Soup and J.M. Smucker are reporting weak sales in the US market. American consumers are turning to healthier meals and snacks. The demand for fresh and healthier food is rising and food makers are struggling to adapt. For many years, processed food rich in sugar, salt and hydrogenated fat has been easy and cheap to produce and sell. Hard pressed consumers living in a fast pace modern life were easily sucked in the “buy one get one free” promotions for TV dinners. As processed food replaced traditional food home cooking vanished. Continue reading “Is Food Consumption Changing in the US?” →

It is the beginning of a new year, and for most Houstonians, weight loss is a priority. The new year resolution for a healthier lifestyle is synonymous with a good diet and the question of what plan to follow for year 2018 assails most of us. Indeed, deciding what to eat on a daily basis has become a dilemma for most of us. Should we adopt a high protein or vegan diet? Should we buy organic or conventional apples? Should we eat butter and cheese or avoid dairy products altogether? Is sugar bad for me even in moderation? And how about soy products, food additives, frozen meals… Continue reading “Best Diet for 2018” →

“The Meals That Still Matter” is a well written article I have recently enjoyed reading in the Wall Street Journal. Bee Wilson, a British food writer and journalist, is the author. She reports that “Holidays are now the only time of the year when we really focus on what and how we eat”. Wilson further adds: “In our daily meals, we have become starved for ritual, which can make it feel as if life has lost its rhythms… Continue reading “Holiday Meals Still Matter” →

The American Society for Metabolic and Bariatric Surgery (ASMBS) funded a survey of 1509 adults representing the US household population. The survey was completed in 2016 and aimed at evaluating public perception of obesity. Continue reading “Obesity in America” →

I read with great interest the recent study by Valdearcos et al titled “Microglial Inflammatory Signaling Orchestrates the Hypothalamic Immune Response to Dietary Excess and Mediates Obesity Susceptibility” and published in the journal of Cell Metabolism. The authors neatly demonstrate that hypothalamic microglia rapidly increase in response to high fat diet in a mouse model. Increased microglia result in increased inflammation in the hypothalamus and neuronal stress. This is turn leads to reduced sensitivity to homeostatic signals like leptin leading to over-consumption and weight gain. This study represents the first evidence linking dietary over-consumption and hypothalamic dysfunction leading to fat accumulation. Center to hypothalamic dysfunction is increased inflammation caused by increased microglia. Microglia are macrophage cells and are the first and main immune defense in the brain. They typically respond to infections but in the case of obesity they respond to excess dietary fat.

It is quite refreshing to read such studies that demonstrate the role of the hypothalamus in energy metabolism and obesity. The hypothalamus regulates body weight the same it controls body temperature. Unless the set point for body weight is altered weight gain, or loss cannot occur. Increased inflammation mediated by the immune system in response to increased fat consumption seems to alter the hypothalamic set point for body weight. Excessive food consumption or consumption of certain types of nutrients like saturated fats causes immune system over-activation. This in turn leads to chronic inflammation. Valdearcos et al nicely show that chronic inflammation in the hypothalamus reduces its ability to respond to leptin leading to obesity. Hundreds of neuro-hormonal signals convey messages to the hypothalamus from peripheral organs like the gastro-intestinal tract, pancreas, liver and adipose tissue. The hypothalamus integrates these messages to maintain a stable body weight. It would be interesting to study the effect of sleeve gastrectomy and gastric bypass surgery on hypothalamic inflammation. Weight loss surgery resets the hypothalamic set point for body weight. Does weight loss surgery decrease hypothalamic microglia and associated inflammation? We know that GLP-1 and PYY increase after weight loss surgery. It is possible for such an increase to overcome the hypothalamic resistance to respond to such signals. With decreased calorie intake and increased hypothalamic response to gut signals, weight loss surgery achieves durable and significant weight loss. Calorie restriction by itself, without restoring the hypothalamic set point of body weight, is not likely to resolve the underlying pathophysiology of obesity.