Feel like you’re eating healthy, yet still can’t lose the last few pounds? It may be when, not what you’re eating.
Everyone’s body is different, so it only makes sense that the healthiest diet for each of us is going to be slightly different, too.
But, there is one thing we all have in common: the digestion of our food takes hours, we have to sleep, and there are only 24 hours in a day.
Hence, the advice your grandma probably gave you ( I know mine did!) to eat dinner early, before 7pm, is spot on.
The Science Behind Early Dinner for Weight Loss
Intermittent fasting, or time-restricted feeding has been shown to aid in weight loss in both human and animal studies.
The idea is that if you do all your eating for a day within a 9-12 hour window, and fast the remaining 12-15 hours (which is not that hard, if you consider you could be sleeping for 8 of them.)
Research suggests this type of eating pattern leads to lower cancer risk and better odds of maintaining or losing weight, thanks to a metabolic shift to fat metabolism and ketone production. (1)
Anecdotally, I know when I personally do this, I wake up with a flatter stomach, have better digestion, and find it easier to maintain a lower weight compared to when I eat at all hours of the day, especially right before bed.
In a 2012 study, researchers at the Salk Institute for Biological Studies found that when mice were given the same high fat diet, those that were restricted to eating within an eight hour window gained little weight and developed no metabolic issues, meanwhile, those that ate the same diet at all hours of the day, gained weight and developed metabolic problems. (2)
A later study published in the Journal Cell Metabolism, found similar, and even more compelling results. Researchers divided mice into 4 dietary groups: high fat, high fructose, high fat and high fructose, and regular kibble. Those groups were each further divided so that some of the mice ate this diet all day long, while the others were restricted to a feeding window of 9, 12, or 15 hours. The caloric intake for all mice was the same.
Here are the fascinating results:
- Over the course of 38 weeks, those in the 9 or 12 hour time restricted groups remained thin and healthy, meanwhile their counterparts eating the same diet without time restriction became obese and metabolically ill.
- A few of the mice in the time restricted groups were allowed to cheat and eat all day on the weekends – and they still maintained their more desirable results.
- Meanwhile, the mice who had become obese, and were switched to the time restricted diet during the study, lose some of the weight they had gained.
- The mice that ate the regular kibble on a time restricted plan had less body fat than those who ate all day long. (3)
In short, researchers demonstrated that intermittent fasting could
- help prevent weight gain and obesity, even without changing calories or what you eat
- protect against metabolic diseases, even if not followed 100% of the time (ie. it’s followed during the week, but not the weekends)
In a randomized controlled trial of 107 women aged 30-45, intermittent fasting was effective for improving weight loss, insulin sensitivity and other health biomarkers. (4) More human studies need to be done, but the research we currently have seems promising.
Should You Try Intermittent Fasting?
Practicing intermittent fasting, by restricting eating to a 9-12 hour window may aid in weight loss, even when you keep calories the same. It’s a simple, free, relatively easy to implement technique, so if you currently eat late at night or all day long, and have weight to lose, it’s worth a try.
How to Intermittent Fast
When you intermittent fast, you still eat the same amount and types of food you usually do, just squeeze it into a shorter time window.
And while the animal research suggests you can still have favorable outcomes using this method even when eating junk food, this is not a free pass to eat junk food. For optimum overall and long lasting health, you still want to be eating the healthiest foods, aka REAL FOOD.
The clock starts the second you sip anything that’s not water. It’s not hard, as long as you plan. You can experiment with different patterns, starting with eating in a 12 hour window for a few weeks, and then later a 9 hour window if you feel up to it. Always listen to your body.
Here’s a chart to help you figure out possible meal time patterns:
|First Meal Next Day
|12 hour window
|9 hour window
|6 hour window
You don’t necessarily have to intermittent fast every day to see results – even 3-5 days a week may make a difference.
Personally, I find finishing dinner by 7pm is generally easy for me, and then I can eat breakfast at 7am or 10am the next day. I always listen to how my body feels – it’s easy to get into the habit of making breakfast as soon as you get up, but I find, I’m often not hungry, and can start my day and work for hours before I need something. Always listen to your body.
Have you tried intermittent fasting? If so, what results have you seen?