A Weird Eating Schedule
In a 2012 Hebrew University study, mice fed high fat foods sporadically gained more weight than mice that ate a similar diet on a regular schedule. Researchers suspect that eating at the same times every day trains the body to burn more calories between meals.
The fix: Learn the best times to eat—and stick with them.
Pesticides In Produce
Organochlorines (chemicals in pesticides) can interfere with your body's energy-burning process and make it harder to lose weight, according to a Canadian study. Researchers found that dieters who ate the most toxins experienced a greater-than-normal dip in metabolism and had a harder time losing weight.
The fix: Splurge for the organic versions of these 14 dirty fruits and veggies—the ones grown with the highest levels of pesticides.
Skimping On Sleep
A 2012 study found that people who sleep less move less the next day, which means they burn fewer calories. But it gets worse: Sleep deprivation actually reduces the amount of energy your body uses at rest, according to the German and Swedish researchers.
The fix: Try these 15 tricks to sleep better tonight.
You lose iron during your period every month, and iron helps carry oxygen to your muscles. If your iron levels run too low, your muscles don't get enough O2, your energy plummets, and your metabolism sputters, says Tammy Lakatos Shames, author ofFire Up Your Metabolism: 9 Proven Principles for Burning Fat and Losing Weight Forever.
RELATED: The Foods You Need To Help Fight PMS
Eating Too Little
When you skimp on calories, your body switches into starvation mode, slowing your metabolic rate to conserve the fuel it's got.
The fix: Make sure you get at least 1200 calories per day.
Sitting Too Long
It takes only 20 minutes in any fixed position to inhibit your metabolism, according to Carrie Schmitz, an ergonomic research manager for Ergotron.
The fix: Try taking a walk on your lunch break and go for regular breaks.
Your internal clock directly controls the part of your cells that keeps your metabolism chugging along. But when you disrupt your so-called circadian rhythm—by crossing time zones, for instance—your cells don't function the way they should and your metabolism suffers, according to researchers at the Center for Epigenetics and Metabolism at University of California - Irvine.
The fix: Combat the negative effects of flying by washing your hands often, keeping moving to avoid deep vein thrombosis, sunlight is also key to helping your brain and body adjust.
Not Getting Enough Calcium
Another reason to drink your milk: Calcium plays a key role in regulating your fat metabolism, which determines whether you burn calories or store them as fat. A diet that's high in calcium could help you burn more fat, according to research conducted at the Nutrition Institute at the University of Tennessee at Knoxville.
The fix: Load up on these calcium-rich foods.
All of your body's cellular processes, including metabolism, depend on water. If you're dehydrated, you could burn up to 2 percent fewer calories, according to researchers at the University of Utah.
The fix: Try to drink 8 glasses or 2 L of water per day and an extra 1 L for every hour of exercise.
When you miss breakfast, you don't just set yourself up to overeat at lunch. You actually tell your body to conserve energy—which means it burns calories more slowly. That's one reason a study from the American Journal of Epidemiology found that people who skip a morning meal were 4.5 times more likely to be obese.
The fix: See the best breakfast for weight loss.