I've written a lot about how factors beyond calories - such as meal size, balance, and timing - affect your ability to lose weight and improve your health. A new study in The American Journal of Clinical Nutrition confirms what I've observed during the 20-plus years of my personalized nutrition counseling practice. And that is, having your larger meal at dinner or at lunch can make the difference between losing and not losing weight, even if the same food - and the same calories - are eaten.
This clinical trial - the gold standard type of study, because it controls all conditions so it can determine a cause and effect - took 80 randomly assigned healthy overweight or obese women and fed one group a larger meal at lunch and a smaller meal at dinner for twelve weeks. The second group was given the opposite condition: a smaller meal at dinner and a larger meal at lunch.
The groups experienced significantly different results. While both groups lost weight, the small dinner group lost more weight. They also achieved a lower fasting insulin and improved insulin resistance, a precurser to diabetes. Your insulin level is important for your health. Higher insulin levels correlate with a higher rate of heart attack and colon cancer - and possibly other cancers - as it is considered a "growth factor," which increases cellular proliferation in the body.
"Light at night" has been my mantra since I first started working with clients, though it was poo poo'd by so many of my colleagues and doctors through the years. Well, science is finally starting to catch up with my recomendations!
A ground-breaking study published in The Lancet medical jpurnal in 1953 found that London bus drivers experienced an increased risk of heart disease compared with conductors. Since then, study after study have confirmed that hours of sitting are correlated with chronic diseases, such as type 2 diabetes, heart disease, many cancers, and early death. This statistic is frightening as it means that we desk jockies are doomed.
Today, being sedentary is the norm. Data from high-income countries suggest that the majority of our time being awake is spent being sedentary. That said, high amounts of sedentary behavior has been associated with increased risk for several chronic diseases and early death. This begs the question: if you're active enough, can these negative health outcomes be reversed?
A new review of 16 studies and one million people published in The Lancet looked at hours of sitting and hours of excerise. While this review confirmed the association between sitting and increased death, there was one exception. People in the highest exercise group, who exercised 60 to 75 minutes per day, did not experience adverse effects of sitting, even if they sat 8 hours per day - that is, unless the sitting involved 5 hours ofTV viewing or more per day.
Trying to lose weight and stay fit seems daunting at times. The proof of our universal difficulties is evident when you consider that most of us -two-thirds of the U.S. population - tip the scales with numbers higher than medical authorities say is healthful.
The origin of the frustrations we're facing today can be traced back 100,000 or more years. By then, our genetic code had been established during millions of years of evolution, and it hasn't changed much since. We evolved in an environment where food was scarce; and we faced regular famines. To overcome these obstacles, we developed a strong appetite for food which enabled us to survive. If you didn't have a strong appetite, you didn't survive through the regular famines. And we, my friends, are descended from the survivors! We have very strong appetites and love our food! Think about it: a loss of appetite is usually a sign of sickness, or even dying.
But in the relative affluence of modern life, our appetites may now cause us grief - and girth. So how do we lose weight, that is - take in fewer calories than we burn - and not feel hungry? A recent study looked at this question. It pitted increased exercise against a 25% calorie restriction to see which one would made us feel hungrier (that means calorie intake was 25% lower than the level of calories that would maintain weight).
Compared with exercise alone, a 25% calorie restriction "created a greater challenge to appetite," according to the study recently published in the Amerian Journal of Clinical Nutrition. It increased the hunger hormone, ghrelin, which upped appetite, made food more attractive, caused more snacking, and less successful weight loss.
But this study had a major downfall - the severe calorie restriction - 25% - in the calorie restricted group. I don't recommend a 25% calorie reduction as it's much too low to be sustainable. In fact, I've found if meals are balanced correctly with the right kinds of foods, including foods you enjoy, if the timing of meals is right, and there's at least a minimal amount of physical activity, you can lose weight while feeling satisfied. But, I also agree with the study: if there is no physical activity at all, then a stricter calorie reduction would probably be necessary - making your program impossible to have lasting results.