Weight gain occurs if you consume more calories than you burn daily, regardless of what time of day you eat the calories. If you're eating late, heading straight to bed and the number on the scale is going up, it's possible that you're eating too much. Analyze your entire day's caloric intake and your physical activity to pinpoint the cause of your weight gain.
Why You Gain Weight
A pound of fat stores 3,500 calories; when you eat 3,500 more calories than you burn, you'll gain a pound. Even a small calorie surplus adds up; just 100 calories in excess of your daily needs each day can cause you to gain more than 10 pounds in a year.
It doesn't matter what time of day you add those calories; it may be an extra couple of tablespoons or cream in your morning coffee, a cookie at snack time, an extra ounce of cheese on your lunchtime sandwich or a second glass of wine at dinner. Sleep itself doesn't cause weight gain -- excess calories do.
Why You're Falling Asleep Right After Dinner
Why you fall asleep right after dinner might be a reason for your weight gain. Work stress could be making you arrive home late, hence your late dinner and immediate bedtime. This stress causes you to crave unhealthy foods and makes your body pump out the hormone cortisol, which encourages fat storage. When all you have time for is work, sleeping and eating, you're bound to gain pounds.
Stress and late work hours or other obligations may also be interfering with your workout schedule, preventing you from hitting the gym to burn the calories necessary for weight maintenance.
If you're falling asleep right after dinner because you're overtired, you may not be getting the requisite seven to nine hours of uninterrupted sleep per night recommended by the National Sleep Foundation. If you don't sleep enough, hormones that regulate your sensations of hunger increase and the ones that register feelings of fullness decrease. You may unknowingly be eating more because you feel hungrier.
Spreading Out Your Calorie Intake
Some people fall into the habit of skimping on meals early in the day only to overeat at dinnertime. You may actually eat more overall when you follow this pattern and consequently gain weight. When you're extremely hungry, it's harder to make healthy dietary choices; you may reach for pizza, fast food or processed snacks just to fill you up. These foods have more calories and less fiber and protein than a meal containing grilled meats, vegetables and whole grains -- nutritional qualities that help you maintain a healthy body size.
Estimate your daily calorie needs using an online calculator that takes into account your age, size, gender and activity level, which will tell you how many calories you need to maintain weight. Divide these calories out over three meals and two snacks. This more regular distribution of calories may help you control your hunger more readily so you don't overeat at dinner and exceed your daily calorie goal.
Eating Before Bed May Disrupt Sleep
While eating dinner and then going to bed isn't directly going to cause you to gain weight, it could disrupt your normal circadian rhythms so that weight gain is more likely. If you eat particularly late, when your body senses it should be sleeping, you experience a rise in blood sugar, which your body isn't able to handle effectively because it's shut down metabolically for bedtime. Overtime, this can lead to insulin resistance and metabolic disorders, a side effect of which is weight gain.
Heartburn can also result if you eat a large meal and immediately lie down to sleep. This disturbs the quality of your sleep and could, thus, interfere with your hunger hormones, causing you to have more cravings the next day. When you indulge these cravings, you gain weight.
Finish your meal and 1 1/2 to 2 hours before bedtime to assist digestion. Don't skip dinner if you're hungry and must go to bed soon, though. Skipping a meal can make you wake in the night famished and lead to overeating at your next meal.