Eating is a part of life; it’s something we do every day and for most of us all the time. From early in the morning to late at night. When people are asked to remember what and when they eat, the amount is underestimated, and the nibbles don’t appear on any timeline. It’s as if the memory can’t keep up with what we put in our mouths.
With many of us looking to change our eating habits, how do we go about it is an important question. There is tons of advice about healthy eating and what you should be eating. Anything from fermented foods to whole grains to plant-based. To meat or not? The choices are endless.
There are questions around the macro-nutrients we should be consuming, from low carbs to high carbs, low protein to high protein or low fat to high fat.
The what and how to eat have got a lot of press. When you eat and when you don’t get the same air-time. The number of diet books and recipe books runs into the hundreds. There isn’t a lot of money to be made by the food industry or publishing houses around the time we eat – excuse me if my cynical side is showing again.
What about finding an easier way to eat less that doesn’t take too much willpower – coincidentally, willpower doesn’t work. Something that you can do while asleep. Enter TRE.
Time Restrictive Eating (TRE) is exactly what it says on the can and looks at keeping the feeding window to a fixed number of hours in a day.
So what is TRE, why should I do it, and does it work?
It is fasting like a calorie restriction (CR) and intermittent fasting (IF).
As with intermittent fasting plans like the 5:2 or 16:8 diets, you do reduce your calorie intake. Only with TRE, there is an eating window, usually between 8-12 hours.
The reasoning behind time restrictive eating lies in the fact that all people have a circadian rhythm. We wake up in the daylight and go to sleep at night. Our entire body, including our immune system, metabolic rate and stress response, follow a circadian rhythm. Whenever this is disrupted, we know about it. Ask anybody who’s experienced jet lag. The rapid change in rhythm is plain to see.
The day-night pattern is driven largely by the hormone melatonin. In the early hours of the morning, our melatonin level starts to fall, and we awaken. Sometime in the evening, around 8 pm, melatonin levels rise. This signals to our body that it’s time to go to sleep. By about 10 pm, your core temperature and metabolic rate drop. In effect, your body is saying the engine is on low revs, so I don’t need more petrol.
The problem arises when we continue to feed the engine by eating. During the daytime, the carbs we eat cause a rise in insulin, which burns mainly sugar. The same amount of food doesn’t result in the same amount of insulin produced in the night. Strange but true.
This is down to melatonin which turns down insulin production by the pancreas. Until very recently, it was thought that melatonin acted as the sleeping policeman in your brain. There are recently discovered melatonin receptors in our pancreas, the organ that produces insulin. So this hormone that is telling you to go to sleep is also saying to the pancreas you don’t need to produce so much insulin. While some are still produced, it’s not nearly as much as in the daytime.
When I come along and continue to eat late at night, a couple of things happen. The body doesn’t convert the food to energy but stores it preferentially as fat. This means that the stored fat we already have doesn’t get used, making the pile bigger.
Our bodies store glucose in the liver and muscle as glycogen. In the liver, there’s about an eight hour supply which gets used up as we sleep. As the number of glycogen drops, the level of fat burning increases. So if you increase the time of not eating from eight to twelve or sixteen hours, this has a greater effect on lowering your fat stores.
TRE is one way of helping to keep our bodies in shape by stopping the fat stores from growing. When we look at the normal day and rhythms, we’ll see that the metabolic rate goes down at night, and the heat produced by eating (thermic effect) also goes down. So the idea of throwing more food at our bodies, just as it’s winding down, is one sure way of building fat.
Researchers like Sachin Panda of the Salk Institute have found that TRE preserves muscle mass and may increase it. When animals are studied, there is even an increase in endurance. People who have tried TRE to lose weight have not found it to be a magic bullet. Weight loss is small and could depend on how many snacks you cut down in the fasting period. But what a lot of people have found is a better sleep pattern, especially in those who have acid reflux.
Other reasons to try TRE include reducing the risk of type 2 diabetes. In 2019 one study showed a lowering of blood pressure, body fat and glucose levels—all good things in helping to prevent cardiac disease. For the more athletic-minded, when TRE is combined with strength training, there is a loss of fat without losing muscle over twelve weeks. In fact, the opposite has been suggested to be the case where a muscle is more apparent.
It’s important to realise that there is never a size fits health. We are too individual for this approach. TRE could produce the greatest benefit for people who are not suffering an acute illness and not taking diabetic medication. It takes no equipment and is simple to do.
Well worth trying and may even improve your health and bank balance in the process.
Warning: ALWAYS check with your doctor before starting if you have underlying health problems.