Stephen Colbert may be on to something. UCLA Center for Human Nutrition researchers divided study participants into two groups, each of which were fed a nearly identical low-cal diet for 12-weeks. The only difference between the groups was what they were given to eat as an afternoon snack. One group ate 220-calories of pretzels while the other group munched on 240-calories worth of pistachios. Just four weeks into the study, the pistachio group had reduced their BMI by a point, while the pretzel-eating group stayed the same, and their cholesterol and triglyceride levels showed improvements as well.
"A study by David Jenkins, MD, PhD—the University of Toronto pioneer in low-glycemic eating — demonstrates that eating small portions at frequent intervals is good for your health in a number of remarkable ways. Within the study, they found that people who ate every three hours reduced their blood cholesterol by over 15% and their blood insulin by almost 28%. That's key, because in addition to regulating your blood sugar level, insulin plays a pivotal role in fat metabolism, inflammation and the progression to metabolic syndrome. When your body produces less insulin, you're much less likely to convert dietary calories into body fat.
Don't get me wrong — exercising at any time is good for you. But evening activity may be particularly beneficial because many people's metabolism slows down toward the end of the day. Thirty minutes of aerobic activity before dinner increases your metabolic rate and may keep it elevated for another two or three hours, even after you've stopped moving. Plus, it'll help you relax post-meal so you won't be tempted by stress-induced grazing that can rack up calories.
Based on my experience in nutrition counseling, most of us tend to snack on foods that aren’t nutrient-dense, but are high in calories. For example, skipping sugary beverages is often the easiest way to lose weight faster. You don’t feel full from drinks — even the ones that do contain calories — so swapping those out for sparkling water or unsweetened tea and coffee is the best place to start. Other major culprits often come in refined grains like cereals, chips, crackers, and cookies.