The Truth About Eating At Night & Fat Loss

“Eat breakfast like a king, eat lunch like a prince and eat dinner like a pauper.” This maxim can be attributed to nutrition writer Adelle Davis, and since her passing in 1974, the advice to eat less at night to help with fat loss has lived on and continued to circulate in many different incarnations. This includes suggestions such as:

• “Don't eat a lot before bedtime”
• “Don’t eat midnight snacks”
• “Don’t eat anything after 7pm”
• “Don’t eat any carbs at night”
• “Don’t eat any carbs after 3 pm”

...and so on.

I too believe that eating lightly at night is usually very solid advice for people seeking increased fat loss, especially for people who are inactive at night. However, some fitness experts today, when they hear “eat less at night,” start screaming, "Diet Voodoo!”…

Opinions on this subject are definitely mixed. Many highly respected experts strongly recommend eating less at night to improve fat loss, while others suggest that it’s only "calories in vs calories out" over 24 hours that matters.

The critics say that it’s ridiculous to cut off food intake at a certain hour or to presume that “carbs turn to fat” at night as if there were some kind of nocturnal carbohydrate gremlins waiting to shuttle calories into fat cells when the moon is full. They suggest that if you eat less in the morning and eat more at night, it all “balances itself out at the end of the day.”

Of course, food does not turn to fat just because it’s eaten after a certain “cutoff hour” and carbs do not necessarily turn to fat at night either (although there are hypotheses about low evening insulin sensitivity having some significance). What we do know for certain is that the law of energy balance is with us at all hours of the day - and that bears some deeper consideration when you realize that we expend the least energy when we are sleeping and many people spend the entire evening watching TV.

I had the privilege of interviewing sports nutritionist and dietician Dan Benardot, PhD, and he gave us a very interesting perspective on this.

Dr. Benardot said that thinking in terms of 24 hour energy balance may be a seriously flawed and outdated concept. He says that the old model of energy balance looks at calories in versus calories out in 24 hour units. However, what really happens is that your body allocates energy minute by minute and hour by hour as your body’s needs dictate, not at some specified 24 hour end point.

I first heard this concept suggested by Dr. Fred Hatfield about 15 years ago. Hatfield explained how and why you should be thinking ahead to the next three hours and adjusting your energy intake accordingly.

Although it’s not really a new idea, Dr. Benardot has recently taken this concept to a much higher level of refinement and he calls the new paradigm, “Within Day Energy Balance.”

The Within Day Energy Balance approach not only backs up the practice of eating small meals approximately every three hours, AND the practice of “nutrient timing” (which is why post workout nutrition is such a popular topic today, and rightly so)… it also suggests that we should adjust our energy intake according to our activity.

Let’s make the assumption most people come home from work, then plop on the couch in front of the TV all night. Let’s also assume that the majority of people go to bed late in the evening, usually around 10 pm, 11 pm or midnight. Therefore, nighttime is the period during which the least energy is being expended.

If this is true, then it’s logical to suggest that one should not eat huge amounts of calories at night, especially right before bed because that would provide excess fuel at a time when it is not needed. The result is increased likelihood of fat storage.

From the within day energy balance perspective, the advice to eat less at night makes complete sense. Of course it also suggests that if you train at night, then you should eat more at night to support that activity beforehand and to support recovery afterwards.

Those stuck on a 24 hour model of energy expenditure would say timing of energy intake doesn't matter as long as the total calories for the day are in a deficit. But who ever decided that the body operates on a 24-hour “DAY”?

Try this test (or not!): Eat a 2500 calorie per day diet, with nothing for breakfast, nothing before or after your morning workout, 500 calories for lunch, 750 calories for dinner and 1250 calories before bedtime.

Now compare that to the SAME 2500 calorie diet with 6 small meals of approximately 420 calories per meal and then tweak those meal sizes a bit so that you eat a little more before and after your workout and a little less later at night.

Both are 2500 calories per day. According to “24 hour energy balance” thinking, both diets will produce the same results in performance, health and body composition. But will they?

Does your body really do a calculation at midnight and add up the day’s totals like a business man when he closes out the register at night? It’s a lot more logical that energy is stored in real time and energy is burned in real time, rather than accounted for at the end of each 24 hour period.

24 hour energy balance is just one way to academically sort calories so you can understand it and count it in convenient units of time. This has its uses, as in calculating a daily calorie intake level for menu planning purposes.

Ok, but enough about calories, what about the individual macronutrients? Some people don't simply suggest eating fewer calories at night, they suggest you take your calorie cut specifically from CARBS rather than from all macronutrients evenly across the board. Is there anything to it?

Well, there’s more than one theory. The most commonly quoted theory has to do with insulin.

The late bodybuilding guru Dan Duchaine was once asked by a competitor,

“I want to get cut up for an upcoming contest. Should I eat at night? I heard I shouldn’t eat carbs after six pm.”

Duchaine answered:

“It’s true that insulin sensitivity is lowest at night. Let’s discuss what is happening in your body that makes it dislike carbs at night. Cortisol, a catabolic hormone, is highest at night. When cortisol is elevated, your muscle cell insulin sensitivity is lowered…”

More recently, David Barr wrote a tip on “lower carbs at night” for T-Muscle Magazine. He said:

“Even when bulking, you don’t want to start scarfing down Pop Tarts before you go to bed. Our muscle insulin sensitivity decreases as the day wears on, meaning that we’re more likely to generate a large insulin response from ingesting carbs. Stated differently, we’re more predisposed to adding fat mass by eating carbs at night because our body doesn’t handle the hormone insulin as well as it does earlier in the day.”

Mind you, Barr is a not a “voodoo” guy; he is a respected scientist who also happens to be well known as a “dogma destroyer” and “myth buster”… and Duchaine, although he had a shady past and some run-ins with the law, was nevertheless highly respected by nearly all in the bodybuilding world for his ahead-of-his-time nutrition wisdom.

As a result of advice like this, word got out in the bodybuilding and fitness community that you should eat fewer carbs at night. Real world results and the “test of time” have suggested that this is an effective strategy. I also don’t know a single nutrition or training expert who doesn’t agree that insulin management and improvement of insulin sensitivity aren’t effective approaches in the management of body fat.

However, it’s only fair to point out that not all scientists agree that cutting carbs at night will have any real world impact on fat loss, outside of any additional calorie deficit created by it. Dr. Benardot, for example, doesn’t think there’s much to it. He says that exercisers and athletes in particular, usually have excellent glycemic control, so the ratio of macronutrients should not be as much of an issue as the total energy balance in relation to energy needs at a particular time and the meal frequency (eating every 3 hours).

Regardless of which side of the “carbs at night” debate you lean towards, if you consider the within day energy balance principle, it makes perfect sense not to eat large, calorie-dense meals late at night before bedtime.

Keep in mind of course, that cutting back on your calories and/or carbs at night makes the most sense in the context of a fat loss program, especially if fat loss has been slow. It’s quite possible that I might give the exact opposite advice to the skinny “ectomorph” who is having a hard time gaining muscular body weight.

Also consider that this doesn’t necessarily mean eating nothing at night; it may simply mean eating smaller meals or emphasizing lean protein and green veggies (or a small protein shake) at night.

Many programs suggest a specific time when you should eat your last meal of the day. However, I’d suggest avoiding an absolute cut off time, such as “no food or no carbs after 6 pm, etc,” because people go to bed at different times, and maintenance of steady blood sugar and an optimal hormonal balance even at night are also important goals.

A more personalized suggestion is to cut off food intake 3 hours before bedtime, if practical and possible. For example, if you eat dinner at 6 pm, but don’t go to bed until 12 midnight, then a small 9 pm meal or a snack makes sense, but keep it light, preferably lean protein, and don't raid the refrigerator at 11:55!

An important rule to remember in all cases, is that whatever is working, keep doing more of it. If you eat your largest meal before bed and lose fat anyway, I would never tell you to change that. Results are what counts. On the other hand, if you’re stuck at a fat loss plateau, this is a technique I’d suggest you give a try.

Night time eating is likely to remain a subject of debate - especially the part about whether carbs should be targeted for removal in evening meals.

However, perhaps even those who are skeptical can consider, that if cutting out carbs at night is effective for fat loss, it may be for the simple reason that it forces you to eat less automatically.

In other words, setting a rule to eat fewer calories or to eat fewer carbs at night may be a very effective way to keep your daily calories in check and to match intake to activity, whereas people who are allowed to eat ad libitum at night when they’re home, glued to the couch and watching TV, etc., may tend to overeat when food is readily available, but the energy is not needed in large amounts.

Me personally? Unless I’m weight training at night, I have always reduced calories and carbs at night when “cutting” for bodybuilding competition. It’s worked so well for me that I devoted a whole section to it in my program, Burn The Fat, Feed The Muscle (BFFM) and I call the techniques “calorie tapering” and “carb tapering.”