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Feeding Window Metabolism and Health


What is a Feeding Window?

Your feeding window starts with your first meal after waking and ends with your last meal before going to sleep. Read part 1 (click here) to learn how to determine your feeding window.

Let’s explore why your feeding window plays an important role in weight loss and health. Your body has many systems that play off one another and are time dependent. We have a central clock system located in our brain and many of our internal organ systems have their own separate clocks. Your body uses chemicals in the form of hormones and neurotransmitters to communicate and regulate all of these clocks. When operating properly it’s a smooth process. Your feeding window will have a profound impact on this process.

Food is a major trigger affecting your body's various clock systems. We are designed to be in a feeding mode while awake and a fasting mode while asleep. This allows our body to make energy from the foods we eat for our daily activities and build muscle, bone, etc and go into a restorative mode when asleep. All through the night and until you eat again, your body is regenerating and to do this, it uses fat as a fuel source.

Your natural feeding window is designed to follow sunlight. Ideally your body wants you to be feeding when the sun is out and fasting after the sun sets. Several hours before you wake up your body is preparing for the day. Signals are sent to your digestive tract and liver in preparation for waking up. This is what causes you to feel hungry in the morning. This also coincides with when we are active, providing your body with necessary energy to accomplish your tasks. An important point to keep in mind, your body takes several hours after eating/drinking for the digestion process to be completed.

As the day progresses into early evening your body sends signals for digestion, metabolism and other processes to start slowing down. Your ability to digest food will not be as efficient and will take longer the later you eat/drink.

How your feeding window plays into weight loss and health:

Let’s look first at your last meal/drink and its impact. To optimize digestion for energy and not fat storage, it’s best to finish eating at least 3 hours before bedtime. The later you eat, those calories will be stored mostly as fat. This occurs because you are significantly less active, therefore requiring less fuel for energy. Secondly, your body is preparing for sleep by releasing and diminishing hormones that are slowing down digestion and metabolism. Melatonin is released in small doses to prepare your body for sleep a couple of hours before your habitual bed time. Melatonin also prevents insulin from working at full capacity. The carbohydrates you eat or drink late at night will not be absorbed and will remain elevated in your blood stream. Elevated blood glucose is not healthy and can create a problem if you are diabetic.

Remember, the digestion process slows down later into the evening, so the 3-hour process will take longer to complete. Your body cannot go into restorative mode while your body is digesting the late-night meal. Now your fat burning phase during sleep becomes shorter.

Morning approaches and before you wake or eat your body is switching over to feeding mode. This gives you the energy to be active before eating. (A survival mechanism from our ancestors who didn’t always have food readily available.) You eat breakfast, this kicks in the digestive process, activating your liver and metabolism. Now you are in full building mode for your muscles, brain, bones and energy storage systems. The calories not being burned throughout the day or used to replace fuel will be stored as fat. This process continues throughout your feeding window.

If you delay eating after waking, which keeps you in a fasted state, your body will keep burning fat as fuel. Don’t be fooled into believing this will allow you to eat later into the night. As mentioned earlier, your digestive system slows down in the evening and requires a longer time to complete the digestive process.

To optimize your body’s natural weight management systems, your feeding window should be less than 12 hours, ideally between 8-10 hour. The 8 -10 hour feeding window will optimize digestion, metabolism and other organ functions. Eating in an 8-10 hour feeding window makes overeating more difficult. Due to insulin spikes, spreading food out throughout the day and into the evening will keep your body in fat storing mode.

In summary, to optimize your health and ability to manage your weight you should try to:

1.Delay eating two or more hours after waking (assuming you wake up before 8 am)

2.Keep your eating window between 8-10 hours.

3.Your last meal should be three hours before going to sleep.

Knowledge is power. Learn how food effects your body’s built-in mechanisms for controlling your weight, health and cognitive function. We can provide you with the tools and mechanisms.

To learn how to eat healthy give us a call at 215-830-9997.


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