1. You don’t get good sleep. If you're chronically sleep deprived, don’t be surprised if you gain a few pounds without eating a morsel of extra food. “A lack of sleep can cause several metabolic problems,” says nutritionist Seth Santoro. “It can cause you to burn fewer calories, lack appetite control and experience an increase in cortisol levels, which stores fat.” Lack of sufficient sleep — which experts say is 7 to 9 hours a night for most people — also leads to impaired glucose tolerance, a.k.a. your body's ability to utilize sugar for fuel. “We all have those less-than-adequate nights of sleep,” says nutritionist Lisa Jubilee. “But if it's a regular thing, you're better off lengthening your night's sleep than working out, if fat loss or weight maintenance is your goal.”
2. You started your day dehydrated. For Jubilee, one of the best and cheapest ways to give your metabolism a jolt is to drink water (she suggests 20 to 32 ounces) shortly after waking. Why? During sleep, your body’s metabolic function slowed, and unless you woke up in the middle of the night to swig some water, it didn’t receive any fluids. Jubilee suggests completely rehydrating before stressing your body with any other food or drink. “My clients who have implemented this report less bloating, more energy and a smaller appetite,” she says. Her motto for getting your inner furnace stoked and ready for the day: “Rehydrate, then caffeinate!” And caffeinate with tea.
3. You drank too much caffeine. Plenty of studies indicate that caffeine can boost your metabolism in the AM. But nutritionist Amy Shapiro says that guzzling coffee and other caffeinated drinks all day could actually work against you. Caffeine is a natural appetite suppressant. If you’re constantly consuming it, you may not eat much — or realize how hungry you really are — until you get home for dinner. “Not eating enough throughout the day can make your metabolism sluggish,” she says. “By the time you eat dinner, instead of immediately using that food for energy, your body is aggressively storing it as fat, just in case it will be deprived again.”
4. You sit too much. Ideally, we sleep about eight hours for every 24. Most people spend another seven to ten hours sitting at their desk. That means most of us spend the overwhelming majority of our time sedentary. Our bodies weren't designed for this level of inactivity — most of humans’ evolutionary history involved being active, searching for food and fuel. Jubilee says that one way to burn more calories daily is to stand more and sit less. She cites a British study which found that standing at work burned 50 more calories per hour than sitting. If that doesn’t sound like a lot, consider this: If you stand for just three hours of your day, in one year you’d expend more than 30,000 extra calories — which amounts to about 8 lbs of fat! Another good office habit: Set a phone timer to remind you get up every hour and walk around, even for a few minutes, says Jubilee.
5. You ate too many calories too late in the day. “Not eating enough calories in a day is an easy way to slow your metabolism,” says Santoro. “It’s a common mistake people make.” When you don’t consume enough calories, your body switches into starvation mode, and your brain tells your body to store fat. This can increase cortisol levels, leading to belly-fat storage, which comes with health risks. “Eating a large dinner, especially too close to bedtime, can be detrimental to your metabolism,” says Shapiro. “It’s likely to throw off your inner clock and make you not hungry in the morning, which can ultimately lead to weight gain.” It’s at this point in the day that people are more likely to have an alcoholic beverage, which can bedevil your metabolism even more. “When a person drinks, acetate is formed,” says Santoro. “The body spends time trying to detoxify itself rather than burn calories.” He adds that drinking alcohol can impair protein synthesis and anabolic (muscle-building) hormones. Shapiro suggests that you prepare for busy or unpredictable days by packing healthy snacks to keep you from overeating or making unhealthful food choices.
6. You didn’t eat organic. “Hormones dictate how our body utilizes the energy we give it,” says Jubilee. “Between our reproductive, thyroid and growth hormones, appetite, insulin and hunger hormones — leptin and ghrelin — our bodies have to perform a tricky balancing act to keep us lean, energized and viable reproductive beings.” Those tasks have become much more difficult because of the hormone residues we consume via cage-raised foods. If you want to give your metabolism a leg up, Jubilee says, switch to organic, grass-fed, pasture-raised beef, eggs and dairy products, thereby avoiding those nasty hormones at mealtime.