If you're not eating all day until night, then you're using a type of intermittent fasting. Depending on how you do it, you could see some weight loss or put yourself at risk for health issues.
Not Eating All Day
If you're not hungry during the day but starving at night, you're not alone. Whether it's because you're too busy to eat during the day or you forget to eat because you don't feel hunger pangs, waiting until night and only eating once a day is unhealthy.
While MedlinePlus busts the myth that skipping breakfast will lead to weight gain and that eating at night will make you fat, it does say that fasting isn't healthy if you're hungry all day and finish the day with a meal that replaces all the calories you skipped earlier in the day. Compared to people who lose fat by eating fewer calories, those who fast lose more muscle than fat.
Instead of not eating all day until night, aim to cut the empty calories out of your diet and avoid cutting out meals entirely without medical supervision.
According to the Centers for Disease Control and Prevention (CDC), you should make a list of your eating habits and highlight the ones that lead to overeating. One of these is skipping meals. From there, you should make a list of cues, or things that encourage you to engage in those bad habits. Pay close attention to the cues you deal with daily or weekly. Look for ways to avoid as many of the cues as you can.
In situations where there is nothing you can do to avoid the cue, look for healthier alternatives. For instance, if you're skipping breakfast because you don't have time to eat before work, can you pack a healthy breakfast the night before to eat once you get to work? Can you prepare a week's worth of breakfasts on your days off to make it easy to grab and go?
What Is Intermittent Fasting?
Intermittent fasting refers to fasting for a certain period of time every day or every other day. Not eating all day until night is an extreme form of intermittent fasting known as the one-meal-a-day diet. Essentially, you go hungry for 23 hours a day and give yourself one hour a day to eat. Eating only at night for weight loss can leave you feeling tired during the day because your body doesn't have the energy it needs to function optimally.
When someone refers to intermittent fasting, they could be referring to any number of approaches. A common method is to use the 16:8 method. With this approach, people are fasting for 16 hours a day, and only allow themselves to eat within an eight hour period.
You choose the eight hour period based on what works best for your schedule. There are some people who choose to eat from 10 a.m. until 6 p.m, while others opt to eat from 11 a.m. until 7 p.m. It doesn't really matter the time frame you choose, so long as you stick to the same time frame every day.
Though there are some people who choose to eat one meal for the day with intermittent fasting, there are people that allow themselves to eat multiple small meals throughout the day, so long as they don't eat outside of that eight hour time period.
According to an April 2019 study published in the Proceedings of the Nutrition Society, fasting over a period longer than 16 hours is better for improving insulin sensitivity and decreasing fat mass. The study also indicates that additional research is needed to determine if the health effects of intermittent fasting are attributed to the fasting periods or a result of the negative energy balance that comes from any form of dietary restriction.
Regardless of how it's done, fasting may not present the weight loss effects you'd think. A January 2018 small-scale study with 29 participants published in the American Journal of Clinical Nutrition showed that fasting during Ramadan (Islamic holiday where you fast from sunrise until sunset for a month) did not have an effect on basal metabolic rate, or the number of calories you burn throughout the day while at rest, or weight loss. That's not promising for people who are eating only at night for weight loss.
Eating Too Much at Night
There's nothing inherently wrong with eating at night. It's what and how much people eat at night that ends up being the problem.
According to a January 2013 small-scale study with 52 participants published in Appetite, meal timing influences daily caloric intake. The study results suggest that eating close to sleep could lead to weight gain because of the increased number of eating times and higher daily caloric intake. Another small-scale study with 59 participants, published in the November 2014 issue of Nutrition Research echoed those results.
In a July 2013 study published in Sleep, chronically sleep restricted adults who went to bed late were more susceptible to weight gain because of a greater daily caloric intake and consuming calories during late-night hours.
An April 2013 study published in the International Journal of Obesity showed eating late may influence how successful weight loss attempts are. The idea is that by eating so much late at night, you're not hungry enough to eat in the morning. The cycle of eating only at night for weight loss continues because you end up incredibly hungry again the following night due to not eating enough during the day.
If you have gastroesophageal reflux disease (GERD), then eating only at night for weight loss is not a good idea. According to Mayo Clinic, GERD is a condition that causes stomach acid to flow back into your esophagus. It generally causes heartburn after eating, which is worse at night.
Is This an Emergency?
- MedlinePlus: "Diet Myths and Facts"
- Centers for Disease Control and Prevention: "Improving Your Eating Habits"
- Proceedings of the Nutrition Society: "The Role of Intermittent Fasting and Meal Timing in Weight Management and Metabolic Health"
- American Journal of Clinical Nutrition: "The Effects of Ramadan Fasting on Activity and Energy Expenditure"
- Appetite: "Contribution of Evening Macronutrient Intake to Total Caloric Intake and Body Mass Index"
- Nutrition Research: "Meal Timing Influences Daily Caloric Intake in Healthy Adults"
- Sleep: "Effects of Experimental Sleep Restriction on Weight Gain, Caloric Intake and Meal Timing in Healthy Adults"
- International Journal of Obesity: "Timing of Food Intake Predicts Weight Loss Effectiveness"
- Mayo Clinic: "Gastroesophageal Reflux Disease (GERD)"
- Harvard Health Publishing: "9 Ways to Relieve Acid Reflux Without Medication"
- BMR Calculator