Both night shift work and night eating syndrome (eating at least 25 percent of your daily calories after dinner and/or waking in the middle of the night to eat) are related to weight gain, which may be linked to an impairment of circadian rhythms (body clock).
Growing research — animal studies and now human studies — indicates that eating more of your calories earlier in the day may factor into weight regulation. In a study of 420 individuals, published in the International Journal of Obesity, two groups — early and late eaters — followed a Mediterranean-style diet of similar calorie intake and food composition for 20 weeks. The early eaters consumed their main meal before 3 p.m., whereas the late eaters ate their main meal after 3 p.m. The late eaters lost less weight and at a slower rate.
In a study published in Obesity, 59 people with type 2 diabetes ate two similar diets that differed in calorie distribution over the day. One group consumed 33 percent of daily calories at breakfast, while the other group ate a small breakfast of only 12.5 percent of daily calories. Although there was not a significant difference in body weight, the large breakfast group showed better blood glucose control, blood pressure reductions, and hunger scores.
Impressive results were published in another Obesity study, which included 93 obese women with metabolic syndrome (a clustering of risk factors for chronic disease). They were divided into two diet groups, each containing 1,400 calories. The big-breakfast group received 700 calories at breakfast, 500 calories at lunch, and 200 calories at dinner. The big-dinner group received the reverse: 200 calories at breakfast, 500 calories at lunch, and 700 calories at dinner. In the 12-week study, the average weight loss in the big breakfast group was 17.8 pounds versus 7.3 pounds in the big dinner group.
Although the body systems involved in meal timing and weight loss are not fully understood, scientists believe that satiety hormones, such as leptin and ghrelin, may be involved. And since the body’s metabolism is strongly linked to circadian rhythms, the disruption in the body clock may lead to weight gain. We live in a culture where the norm tends to be eating the main meal later in the day. But if weight management is the goal, eating more of your calories earlier is certainly worth striving towards.
Shifting to a bigger breakfast
Here’s an example of a well-balanced 700-calorie breakfast:
■½ cup dry oats made with 1 cup nonfat milk
■1 cup blueberries
■5.3 ounce nonfat flavored Greek yogurt
■¼ cup walnuts
Totals: 721 calories; 37 g protein; 28 g fat (3 g saturated); 85 g carbohydrates; 9 g fiber