When you eat a day’s worth of food really does make a difference, according to Daniela Jacubowicz, a professor at Tel Aviv University. In a recent study, published in the journal Obesity, she randomized 93 overweight and obese women into 2 groups and followed them for 12 weeks. Both groups ate 1400 calories a day, consuming a healthy variety of poultry, fish, egg whites, vegetables, fruits and whole grains. The ‘breakfast group’ had 700 calories for breakfast, 500 for lunch and 200 for dinner. A sweet treat was included as part of their breakfast, such as a small chocolate bar, to stave off cravings for the rest of the day. The ’dinner group’ had exactly the same foods in reverse order - 200 calories for breakfast, 500 for lunch and 700 for dinner. I presume that their chocolate bar came with dinner.
At the end of 12 weeks, the results were striking. The ‘breakfast group’ lost an average of 19 pounds while the ‘dinner group’ lost 8. Waist circumference decreased by 3 inches in the ‘breakfast group’ compared to 1.4 inches in the ‘dinner group’. Glucose and insulin levels dropped significantly more in the ‘breakfast group’. They did not experience the high spikes in glucose levels that can happen after a meal and are considered dangerous. Triglyceride levels fell 34% in the ‘breakfast group’ but increased by 15% in the ‘dinner group’. Triglycerides are a main form of fat in the body; high levels of triglycerides have been associated with greater risk for heart disease. Average hunger scores were significantly lower in the ‘breakfast group’.
The authors of this study concluded that a high calorie breakfast with reduced intake at night is a useful alternative for the management of obesity. Previous studies from Tel Aviv University also looked at overweight men, and came to similar conclusions. In summary, our metabolism is impacted by the body’s 24 hour circadian rhythm. The time of day we eat can have a real impact on the way our bodies process food.
What are the implications of this study for you, the reader? I am not suggesting a 1400 calorie diet, but a change in when you eat the amount of food that is right for you. Your weight may be just right, or you may be overweight, or too thin. You may be a person who is never hungry in the morning, or who really relishes a big dinner at the end of a busy day. I think it makes sense to ease your way into bigger breakfasts and lighter dinners because of the benefits on glucose and insulin levels, and because of the greater energy you will experience after a hearty (healthy) breakfast. If you are never hungry in the morning, try a very light dinner one night, such as a bowl of cereal or a dish of cooked vegetables. You will probably wake with an appetite. If your usual breakfast is toast and tea, or a pastry and coffee, you may notice that your energy drops mid morning and more coffee is needed to keep you going. When you add healthy protein and whole grains to your breakfast you will notice a smoother feeling of energy that lasts until your next meal. What to do about the big dinner you have always loved? When you start to follow this plan, you may find that you want to make it simpler and smaller without too much difficulty. You may like spending less time cooking. Another benefit from a smaller dinner is feeling more energy in the evening. Having a lot to digest at night makes some people sleepy.
Finally, Professor Jacubowicz suggests an end to late night snacking, in front of the computer or television. She feels that this is a major contributor to the obesity epidemic, causing weight gain and a greater risk of cardiovascular disease, due to the midnight spike in blood sugar.
Sadja Greenwood, back issues at sadjascolumns.blogspot.com