How does your brain respond to food? Some overweight people may be hardwired to overeat.

August 2, 2011

Aug. 1, 2011 — Willpower alone usually is not enough for lasting weight loss; instead, some experts now recommend focusing on the ways in which the brain responds to food rather than solely on personal choice.

In a paper published in the August issue of the Journal of the American Dietetic Association, dietitians at Rush University Medical Center in Chicago conclude that “practitioners should more heavily focus on helping patients overcome the brain-based processes” that make dieting so difficult.This, the researchers say, is especially important because the brains of at least some obese and overweight people may be hardwired to overeat.

Such an approach to weight loss may be more successful over the long term, and it may also help counter the stigma that overweight people often feel when unable to control their urge to eat.

“Even highly motivated and nutritionally informed patients struggle to refrain from highly palatable foods that are high in sugar, salt, and unhealthy fats,” study researcher Brad Appelhans, PhD, a clinical psychologist and obesity researcher at Rush University Medical Center, says in a news release.

Brain’s response to food:
In the paper, the researchers present three brain processes that are associated with both overeating and obesity: food reward, inhibitory control, and time discounting.

Food reward, which includes both the pleasure of eating and the motivation to eat, has been linked to the same brain processes that control our urges for sex, gambling, and substance use. People with a greater reward sensitivity will likely have stronger food cravings, particularly for fatty and sweet foods, the researchers write.

Inhibitory control, or the ability to eat in moderation, is influenced by the part of the brain strongly associated with self-control and planning, the researchers write.

Time discounting is the tendency to prefer short-term rewards over long-term rewards. In the case of obesity, it amounts to choosing the immediate pleasure of eating tasty foods as opposed to the health benefits of abstaining.

These three brain processes, when coupled with an environment in which highly tempting high-calorie, low-nutrition foods are readily available, contribute to overweight and obesity. Understanding those processes and controlling such environments, the researchers conclude, may contribute more to successful and sustained weight loss than focusing solely on personal choice.

They recommend the following strategies:
•    Eliminate high fat-foods from your home and your workplace.
•    Stick to a shopping list of healthy foods when at the supermarket, or shop online so you don’t have to confront tempting foods.
•    Reduce stress, a frequent trigger of overeating.
•    Stay away from all-you-can-eat buffets and restaurants that promote overindulgence.
•    Focus on short-term goals, especially at the beginning of a weight loss program

By Matt McMillen
WebMD Health News
Reviewed by Laura J. Martin, MD

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Why do we choose food for comfort during stress?

July 30, 2011

Great Article from the ScienceDaily (June 29, 2011)

We are one step closer to deciphering why some stressed people indulge in chocolate, mashed potatoes, ice cream and other high-calorie, high-fat comfort foods. UT Southwestern Medical Center-led findings, in a mouse study, suggest that

ghrelin — the so-called “hunger hormone” — is involved in triggering this reaction to high stress situations.

“This helps explain certain complex eating behaviors and may be one of the mechanisms by which obesity develops in people exposed to psychosocial stress,” said Dr. Jeffrey Zigman, assistant professor of internal medicine and psychiatry and senior author of a study appearing online June 23 and in a future print edition of the Journal of Clinical Investigation. “We think these findings are not just abstract and relevant only to mice, but likely are also relevant to humans.”

Scientists know that fasting causes ghrelin to be released from the gastrointestinal tract, and that the hormone then plays a role in sending hunger signals to the brain. Dr. Zigman’s laboratory has previously shown that chronic stress also causes elevated ghrelin levels, and that behaviors generally associated with depression and anxiety are minimized when ghrelin levels rise. In mice, these stress-induced rises in ghrelin lead to overeating and increased body weight, suggesting a mechanism for the increased prevalence of weight-related issues observed in humans with chronic stress and depression.

For this investigation, the researchers developed a mouse model to determine which hormones and what parts of the brain may play a role in controlling more complex eating behaviors that occur upon stress, particularly those that lead to the indulgence of comfort foods.

They subjected mice to a standard laboratory technique that induces social stress by exposure to more dominant “bully” mice. Such animals have been shown to be good models for studying depression and the effects of chronic stress and depression in humans.

Wild-type mice subjected to the stress gravitated toward a chamber where they had been trained to find pleasurable, fatty food — the mouse equivalent of “comfort food.” However, genetically-engineered mice, which were not able to respond to stress-induced increases in ghrelin, showed no preference toward the fatty food-paired chamber, and when exposed to the fatty food, did not eat as much as the wild-type animals.

“Our findings show that ghrelin signaling is crucial to this particular behavior and that the increase in ghrelin which occurs as a result of chronic stress is probably behind these food-reward behaviors,” Dr. Zigman said.

The study also showed that these effects of ghrelin are due to direct interaction with a subset of neurons that use catecholamines as a neurotransmitter. These include dopaminergic neurons in the brain’s ventral tegmental area, which is known to be associated with pleasure and reward behaviors.

The findings, he said, may make sense when considered from an evolutionary standpoint.

Our hunter-gatherer ancestors needed to be as calm as possible when it was time to venture out in search of food, or risk becoming dinner themselves, said Dr. Zigman, who pointed out that ghrelin’s anti-depressant effects and its actions to help efficiently secure calorically-dense, tasty foods may have provided a survival advantage.

“Though it might have been beneficial to have these actions of ghrelin linked, now it seems to be a cause of a lot of morbidity in our modern society,” Dr. Zigman said. “Ultimately, these linkages also may present a large challenge to the development of therapeutics to treat and/or prevent obesity.”  The researchers next plan to investigate the molecular mechanisms by which ghrelin acts to cause these stress-associated food-reward behaviors.

The work was supported by the National Institutes of Health, the Foundation for Prader-Willi Research, the Klarman Family Foundation, the National Alliance for Research on Schizophrenia and Depression, and the Disease-Oriented Clinical Scholars Program at UT Southwestern.

Journal Reference:

  1. Jen-Chieh Chuang, Mario Perello, Ichiro Sakata, Sherri Osborne-Lawrence, Joseph M. Savitt, Michael Lutter, Jeffrey M. Zigman. Ghrelin mediates stress-induced food-reward behavior in mice. Journal of Clinical Investigation, 2011; DOI: 10.1172/JCI57660
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What is the 80/20 rule?

June 14, 2010

The 80/20 Rule is pretty simple:

Eat healthy foods 80% of the week, and eat unhealthy foods for the last 20%.  Most people in the United States do the opposite.  20% unhealthy and 80% healthy.  This is why obesity, diabetes, heart disease and cancers have increased.

A healthy diet should contain the following:

  1. Sufficient amounts of proteins (meat, fish, and eggs)
  2. Carbohydrates (bread, starch, pasta, rice)
  3. Fruits and Vegetables (these contain great vitamins and produce fiber
  4. Fats (olive oil, nuts, seeds)

Drinking a lot of water is key too!  It keeps you full and our body consists mostly of water so if we lose water we need to add it back into our system.  There are plenty of diets out there that are good for you.  If you like fast food, there is the “dash diet”.  There are also plenty of guides for diabetes, high blood pressure and Gastrointestinal issues.

Good luck and happy eating!

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Agave Syrup: an UNSAFE sugar substitute

January 21, 2010

Agave syrup is a man-made sweetener which has been through a complicated chemical refining process of enzymatic digestion that converts the starch and fiber into the unbound, man-made chemical fructose. While high fructose agave syrup won’t spike your blood glucose levels as High Fructose Corn Syrup is reported to do, the fructose in it may cause mineral depletion, liver inflammation, hardening of the arteries, insulin resistance leading to diabetes, high blood pressure, cardiovascular disease and obesity.

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Sleep Deprivation negatively impacts overall health

January 19, 2010

Sleep Deprivation adversely affects cognitive performance (reduces problem solving and decision making skills as well as short-term memory, impairs judgment, reduces logical reasoning and critical thinking, reduces visual attention and processing)

  • Adversely affects mood and emotional well being, including increasing feelings of stress, sadness, frustration, anxiety, and rage
  • Impairs immune function
  • Influences the production and release of important hormones:
  • Increased levels of cortisol which contributes to high blood pressure, a weaker immune system, increase appetite and abdominal weight gain)
  • Negatively influence the production and release of leptin and ghrelin, hormones that affect appetite regulation
  • Reduces the effectiveness of insulin, increasing blood sugar levels and increases the risk of diabetes
  • Can inhibit the nocturnal production and release of growth hormones in men, which may contribute to loss of muscles and reduced metabolic rate
  • There’s a relationship between sleep deprivation and risk of high blood pressure, stroke and the metabolic syndrome
  • Sleep deprivation is also a risk factor for weight gain because it makes it more difficult to exercise and eat well
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