If you are a diet enthusiast who keeps an eye on the latest weight loss trends, you may have heard about Time Restricted Eating (TRE). This is a type of diet where a person eats all meals within a particular time window each day, restricting the calories intake to that time frame. The recommended eating window is usually 8-12 hours, while fasting through the remaining hours of the day. For example, someone on a 10-hour eating window of TRE who has breakfast at 8 am should finish eating the latest meal of the day by 6 pm.
Eat according to your body clock
This concept of diet emphasises the idea that it is not only important to watch what you eat but also when you eat, or the timing of your meals. In fact, this is a result of years of research showing that you should eat according to your circadian rhythm, or in other words, your body clock.
According to the body clock, in a 24-hour day period there is an optimal time for every metabolic process to happen. Your metabolism works more efficiently early in the day than in the evening, so your body is less likely to store food as fat when you eat it in the morning, supporting a healthy weight. A study from Harvard University also shows that you are less tolerant to glucose in the evening, which means your blood sugar can spike more easily when eating late.
The effect of TRE on body weight
TRE has gained increased popularity in the past decade with several scientific studies showing its benefits not only in weight loss but also in metabolic disease. In fact, TRE has a broad role in health by improving insulin sensitivity, sleep, and supporting conditions such as obesity, diabetes and cardiovascular disease.
A study examined the effects of a 10-hour TRE program in overweight healthy adults and showed a 4% weight loss that was sustained for one year. Another study showed that a TRE program in which all calories are consumed in an 8-h window each day, in conjunction with resistance training, decreased fat mass and improved metabolic and cardiovascular biomarkers.
The benefits of TRE as a weight loss approach
- It is an inclusive diet where you do not need to eliminate food groups completely, which usually leads to nutritional deficiencies, intolerances and gut flora disruption.
- It improves compliance as it can be easily followed and incorporated into the individual routine.
- You do not need to be counting calories and starving yourself.
- TRE programs are flexible as eating windows can be decreased over time so the individual can adjust gradually. Also, the number of weekly days TRE is performed can be personalised to suit individual needs.
As with any diet or health protocol, you should be advised and followed by a health practitioner in order to obtain optimal results and, very importantly, do it safely.
Healthy eating tips to optimise your TRE
You do not need to re-invent the wheel in order to eat healthy. The following are long-standing health foundation beliefs, which have been around for a long time and are now backed up by scientific research. Follow them to get optimal results when doing TRE and, at any time:
- Importance of breakfast: Have a large breakfast, make your lunch smaller and eat the fewest calories at dinner (and early in the evening) in order to respect the natural body clock. There is much truth in the old saying “Eat breakfast like a king, lunch like a prince and dinner like a pauper”. A study shows that eating a large breakfast can help you not only lose weight but also improve your levels of good cholesterol and increase insulin sensitivity.
- Importance of protein: Your breakfast should be balanced, protein-rich and eaten within 1 hour of waking up. Research shows that a high-protein breakfast improves weight management, reduces food cravings (including those stubborn sweet cravings) and snacking particularly in the evening.
- Balance is everything: Eat a varied balanced diet based on protein, fibre, complex carbohydrates and vegetables. These nutrients combined help preventing blood sugar crashes or food cravings.
- Quality: Invest in good quality, seasonal food from an organic source.
- Get your sleep right: Have a healthy sleep pattern by sleeping at least 7-8 hours at night and eating during the day. People with sleep issues tend to eat more and at the wrong times.
Ultimately, TRE is a health program which goes beyond weight loss by offering significant extra benefits. It is a sensible diet which teaches individuals how to eat at the right time supporting their natural body rhythm and overall adopting a healthier lifestyle.
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