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    How Your Brain Wants You to Eat

    By Maryann Tomovich Jacobsen, MS, RD

    Tired Woman Eating

    I finally got a scientific explanation for something I intuitively knew: structured eating patterns are beneficial for health and well being. In fact, all mammals have evolved to have a predictable day-night cycle with an “endogenous clock system” set in the brain that runs on a near 24-hour period. This is called “circadian,” from the Latin word circa and diem (about a day).

    According to a recent review article published in the British Journal of Nutrition, when this internal clock system is disrupted, over time, it can lead to hormonal imbalances, sleep problems, susceptibility to diseases like cancer, and even reduce life span.

    And two things that have power to greatly affect our circadian clock system (a person’s sleep-wake cycle) for the worse or better: how and what we eat.

    How We Eat

    According to the lead researcher of the study, Felino R. Cagampang, PhD, Senior Lecturer in the Faculty of Medicine at the University of Southampton in the U.K., there is a food entrainable clock in the brain that can override the light-based circadian clock. It is recommended for people to eat during daylight hours so both clocks are in sync.

    “Circulating levels of most hormones and enzymes involved in the processing of food also show circadian rhythmic patterns in anticipation of when food is available,” he says. “Eating at the right time of the day is important for the efficient processing of the food we eat. It is therefore important that one does not skip breakfast but also avoid eating late at night.”

    But when meal patterns get thrown off, like in the case of shift work, frequent travel, crossing time zones, and busy lifestyles, poor metabolic health can result. For example, key hormones that manage hunger, leptin and ghrelin, work less well when eating patterns are not in sync with circadian rhythms

    When asked about grazing versus sit down meals, Dr Cagampang replies “The problem with ‘grazing’ is that the food you pick on usually does not contain all three of the macronutrients ( protein, carbohydrates, and fat) which hold your hunger for a longer period. Grazing also leads to more frequent insulin rises, which might make you more resistant to the action of insulin.”

    What we eat

    When discussing nutrition, Dr Cagampang explains that reducing the amount of saturated fat in the diet is beneficial, as animal studies show eating too much of this type of fat can disrupt circadian rhythms. He recommends focusing on unsaturated fats instead, such as oily fish (salmon and fresh tuna or mackerel) and sunflower or olive oils. And carbohydrates are better received at breakfast as the body is ready to respond to them to get the day started (think energy!).

    “One is advised to eat a substantial portion of your food intake for the day at breakfast — also a time when most carbohydrates for the day should be eaten (e.g. bread, bagel, waffles, oatmeal, muesli, dairy products, etc.), says Dr Cagampang. “Protein-rich food should also be eaten during the early part of the day (during breakfast and lunch) and should be lessened in the evening.”

    So it makes sense to start with a big breakfast and decent lunch while maintaining a more modest dinner, when the body’s metabolism prepares to slow down and fast for the night.

    Tips on how to deal with time changes

    Changes in schedules are inevitable but they don’t have to wreak havoc on your health and well being. This is what Dr Cagampang recommends:

    “To reduce the time it takes to reset your sleep-wake cycle (i.e. ‘jet-lag’ period), fast for about 12 hours before the time you want be awake. So, if you are a shift worker who needs to start waking up at 1 in the morning, you should start to fast at 1 p.m. the day before. Your body will consider the time you break your fast as your new morning.”

    So if you’re having trouble with eating, sleeping, or an uncontrollable appetite, it might be that your sleep-wake cycle is off. A healthy and predictable pattern of eating might just make all the difference in the world.

    Tell me, do you have a regular eating routine or do you wing it?

    Photo: Hemera

    The opinions expressed in WebMD Second Opinion are solely those of the User, who may or may not have medical or scientific training. These opinions do not represent the opinions of WebMD. Second Opinion are... Expand


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