Vary your daily calories while reducing your overall average. Your body may adjust to a lower but steady calorie intake, meaning it won't draw from your stored fat. To keep your body guessing and your metabolism up, try switching between higher and lower daily calorie intakes. This might help avoid that dreaded weight-loss plateau and improve your willpower.[2]
Do more HIIT: High intensity interval training (HIIT) is as close to a magic pill as we have (except it involves a whole lot more work than just swallowing a capsule—sorry). Not only does it surge your body to max intensity during the workout, but because you’re working so hard, your body can’t deliver enough oxygen in the moment, explains personal trainer Jeremey DuVall. Your muscles accumulate a “debt” of oxygen that then has to be repaid post-workout. This throws your body into a phase of fat burning for hours after you’re done sweating, known as post-exercise oxygen consumption, or EPOC. Plus, super intense circuits like this activate muscle-building hormones like growth hormone and IGF-1, he adds.
6. Selenium: This mineral is crucial to regulating your thyroid, the gland in your neck that regulates your metabolism. What’s more, the thyroid is responsible for producing hormones crucial to an efficient and balanced metabolism. Since selenium is commonly found in seafood like tuna and oysters, most land-locked folks could benefit from a supplement of the stuff.
Lose fat with high-intensity interval training (HIIT). If you're trying to lose weight fast, HIIT training can super-charge your metabolism for upwards of 24 hours after exercising.[27] This means your body will continue burning calories long after you've ended your workout. HIIT burns more calories in less time than steady-state cardio. In one study, researchers looked at two groups, one running for 30 to 60 minutes three times per week, the other doing four to six 30-second treadmill sprints, resting for four to six minutes between each sprint. After six weeks, it was found that the group doing HIIT training lost more weight.[28]
Ansari says alcohol can prevent weight-loss in several ways, including the fact that heavy alcohol intake can stimulate food intake. "Binge drinking can overload the liver. The liver then prioritizes processing alcohol over other nutrients and then stores the protein, carbs, and fat as fat in the body," Ansari explains. The Centers for Disease Control and Prevention (CDC) defines binge drinking as having five or more drinks for men, and four or more drinks for women in two hours. "Also, alcoholic beverages are often mixed with sugar-rich beverages. Drinking more than moderate amounts of alcohol can cause calories to add up quickly." 
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