Does Time Restricted Eating Help Weight Loss?

You may have heard that eating small meals throughout the day helps burn calories, reduces food intake, and enables better appetite control. New scientific data suggests otherwise. When you eat is as important as what you eat.

The Effects of Eating Frequency on Obesity

Eating more than 3 meals a day increases the risk of being overweight or obese.¹ Snacking or eating more than 3 meals a day increases abdominal and liver fat. ² Snacking may increase the sense of hunger.³

In contrast, a systematic review and meta-analysis of randomized controlled trials found that intermittent fasting contributed to a significant decrease in body weight and fat mass in adults.⁴

General Health Benefits from Time Restricted Eating

Time-restricted eating (TRE) is a type of intermittent fasting that involves confining daily food intake to 4 to 10 hours and fasting for the remaining hours. In TRE, a common eating window is eight hours. Most of the body’s fat burning happens 6 to 8 hours after a person has finished the last meal of the day and increases almost exponentially after a full 12 hours of fasting.⁵

Several studies show a regular meal pattern, breakfast consumption, eating a higher proportion of energy early in the day, reduced meal frequency (i.e., 2–3 meals/day), and regular fasting periods can offer the following benefits:⁶

• reduce inflammation
• improve circadian rhythmicity
• increase the body’s resilience to stress
• modulate the gut bacteria so as to discourage inflammation
• increase cells’ ability to recycle

TRE and the Metabolic Syndrome

Metabolic Syndrome (MetS) is a group of health issues that includes elevated blood glucose levels, high triglycerides, hypertension, waist circumference greater than 35 inches in women or 40 inches in men, and low HDL cholesterol. Additionally, it is associated with increased inflammation and a higher risk of blood clots. This serious condition significantly raises the risk of cardiovascular disease, kidney damage, type 2 diabetes, and certain types of cancer. Can time-restricted eating (TRE) help individuals with MetS? Yes!

Researchers investigated the effects of time-restricted eating on metabolic syndrome by reducing participants’ daily eating window from 14 hours or more to a self-selected 10-hour window over 12 weeks. The findings revealed that time-restricted eating resulted in weight loss, improved body composition, lower blood pressure, and decreased levels of lipids that promote cardiovascular disease.⁷

Can Time-Restricted Eating Improve Type 2 Diabetes?

Time restricting eating has the potential to improve type 2 diabetes. Evidence, please!

In a randomized, open-label crossover study, ⁸Dr. Hana Kahleova and her colleagues assigned diets to 54 patients with type 2 diabetes, both men and women aged 30 to 70 years, who were being treated with oral blood glucose-lowering medications. Both groups followed diets with the same macronutrient composition and reduced caloric intake for 12 weeks. One group consumed breakfast and an early lunch within a 6-hour window while the other group ate six smaller meals throughout the day.

The results showed that consuming only breakfast and lunch led to greater reductions in body weight, hemoglobin A1c (HFC), fasting plasma glucose, glucagon levels and an increase in the Oral Glucose Insulin Sensitivity (OGIS) compared to the same caloric restriction divided into six meals.

Fasting plasma glucagon decreased in individuals who ate the two meals a day, whereas it increased in those eating six small meals a day. Glucagon is a pancreatic hormone that causes the liver to manufacture and release glucose. Glucagon is already elevated in individuals who are obese and insulin resistant as well as in type 2 diabetes. High levels of glucagon exacerbate hyperglycemia (high blood glucose).⁹

Meal Frequency	Waist Circumference	BMI Decrease	Fasting Blood Glucose Decrease	Insulin Sensitivity
2 meals/day	2.02 inches loss	1.23	14.04 mg/dL	Up 21
6 meals/day	.53 inch loss	.82	8.46 mg/dL	Up 8.2

The researchers of this particular study concluded that for type 2 diabetes patients on a reduced-calorie diet, having larger breakfasts and lunches may be more beneficial than spreading the calorie intake over six smaller meals throughout the day.¹⁰

In another 12-week study, 120 overweight adults with T2DM were randomized into two groups. The participants in one group limited their food consumption to 10-hour (8:00 am to 6:00 pm) while individuals in the other group consumed food at liberty. What were the results? The levels of triglycerides, total cholesterol and low-density lipoprotein cholesterol improved in the TRE group.¹¹

Be Sure to Eat Breakfast

Research shows that individuals who consistently eat breakfast have a lower risk of weight gain compared to those who skip breakfast. Moreover, those eating their largest meal at lunch or dinner have a greater risk of an increased BMI (body mass index).¹²

For example, the Adventist Health Study 2 concluded that in relatively healthy adults, eating less frequently, no snacking, consuming breakfast, and eating the largest meal in the morning may be effective methods for preventing long-term weight gain. Here is what the researchers observed.¹³

• Subjects who ate 1 or 2 meals/d had a reduction in BMI per year (compared with those who ate 3 meals/day.
• In contrast, individuals eating >3 meals/d (snacking) was associated with a relative increase in BMI. Correspondingly, the BMI decreased in the subjects who had a long overnight fast (≥18 h), and the BMI decreased in those who had a medium overnight fast (12–17 h),
• Breakfast eaters experienced a decreased BMI compared with breakfast skippers.
• Subjects who ate their largest meal at dinner, those who consumed breakfast as the largest meal experienced a significant decrease in BMI and those who consumed a big lunch experienced a smaller but still significant decrease in BMI than did those who ate their largest meal at dinner.

In another study, researchers found that women who consumed breakfast irregularly were at higher risk of type 2 diabetes than were women who consumed breakfast daily. Among irregular breakfast eaters, women with a higher eating frequency (≥4 times/d) had a significantly greater T2D risk  than did women who consumed breakfast daily and ate 1–3 times/day.¹⁴

Morning is the optimal time to metabolize glucose. In the evening, the metabolism of glucose diminishes. That is another reason to omit dinner (supper) if one has diabetes or is obese.

Regularity

We have clock genes in our cells that help to control our circadian rhythms. These internal clocks can be inside either the brain or elsewhere in the body. The most powerful clock is the SCN inside the brain. This central body clock is aligned with light and darkness. There is a neuronal tract from the back of the eye to the SCN. There is also a neuronal tract from the SCN to the pineal gland, which controls melatonin secretion. So, light, coming into our eyes helps control circadian rhythms. Light during the day supports alertness.

Eating also influences our body clocks. For optimal health, we want synchrony between the central and peripheral clocks. Through nutritional cues, the peripheral body clocks and the clock genes are aligned with the central body clock.

If we can align our peripheral body clocks with the central body clock through our meal times, it will help treat and even prevent metabolic diseases like metabolic syndrome, obesity, and type 2 diabetes.

Alternative Strategies

While many obese individuals can consistently eat two meals a day, not everyone can adhere to a very low-energy dietary regimen for several weeks on end. A qualitative study showed that women adhered better to intermittent energy restriction 2 d/wk x 4 months vs previously attempted continuous energy restriction.¹⁵

So, if you are obese and cannot eat just two meals a day, choose at least 2 or 3 set days a week in which you can restrict eating to twice a day. As we have seen, eating more than three meals a day has detrimental health consequences. Individuals who have type 2 diabetes should be consistent in the number of meals they eat.

Conclusions:

If supper is the last meal of the day, make it light, without simple carbs as they can decrease the quality of sleep. Eat breakfast like a king, lunch as a prince, and supper as a pauper is a good adage for optimal fat-burning metabolism. Fasting 12 hours from your last meal to your first meal is advantageous. A 14-hour fast is better yet. Sixteen hours is optimal if you are obese. Do not take any calories in three hours before retirement. If you are taking blood sugar-lowering drugs, be sure to consult with your health care provider as how to adjust your medication.

Wildwood Lifestyle Center specializes in type 2 diabetes reversal, obesity, non-alcoholic fatty liver disease, hypertension, atherosclerosis, our immune optimization, depression, and anxiety.

 

 

 

 

 

 

 

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