Every time we eat or drink, we can thank our metabolism for converting all those calories . Our size, gender, and age all factor into our metabolic rate, but there are also ways to independently control its speed. And the faster our metabolism, the more calories , making that Krispy Kreme breakfast no longer such a big deal. (OK, the donut probably still isn't the best idea.) Here are 11 proven ways to keep that body burning strong.

1. Sleep!

Almost nodding off in line at Starbucks isn't the only downside of not catching enough zzz's. a link between metabolism and sleep, and not getting enough of it may seriously slow metabolism.

2. Drink green tea

Not only does this superfood pack an antioxidant-punch, researchers have found it speeds metabolism as well Diepvens, K, Kovacs, E.M., Vogels, N, et al. Maastricht University, Department of Human Biology, The Netherlands. Physiology & Behavior, 2006 Jan 30;87(1):185-91. Epub 2005 Nov 7.. Plus, it's naturally calorie-free, so there's no reason not to enjoy a mug (or two).

3. Amp up workout intensity

Slow and steady may not always win the race. High-intensity interval training (HIIT), such as interval runs, are quick bouts of intense exercise that can jumpstart metabolism and keep us burning calories long after the workout is over. (Afterburn effect, anyone?) Tabata, I., Irisawa, K., Kouzaki, M., et al. Department of Physiology and Biomechanics, National Institute of Fitness and Sports, Kanoya City, Japan. Medicine & Science in Sports & Exercise, 1997 Mar;29(3):390-5.

4. Don't skip breakfast

It may be time to reconsider hitting snooze in favor of getting up to grab a quick bite before starting the day. Studies show the importance of quick-starting metabolism with breakfast Astbury, N.M., Taylor, M.A., Macdonald, IA. School of Biomedical Sciences, Queen's Medical Centre, University of Nottingham, Nottingham UK. Journal of Nutrition, 2011 Oct;5(5):455-63. Epub 2011 Oct 28. Min, C, Noh, H, Kang, Y.S., et al. Department of Food and Nutrition, Seoul National University, Seoul, Korea. Nutrition Research and Practice, 2011 Oct;5(5):455-63. Epub 2011 Oct 28.. No a.m. appetite? Snack on something small, like a bowl of Greek yogurt.

5. Pump some iron

The weight room isn't only to help bulk up or get lean. Lifting weights can also help speed , making those dumbbells our new best friends .Osterberg, KL, Melby, CL. Dept. of Food Science and Human Nutrition, Colorado State University, Fort Collins, CO. International Journal of Sport Nutrition and Exercise Metabolism, 2000 Mar;10(1):71-81. . Pratley, R, Nicklas, B, Rubin, M, et al. Department of Medicine, University of Maryland at Baltimore, Maryland. Journal of Applied Physiology, 994 Jan;76(1):133-7..

6. Gulp some H20

Drinking enough water is a simple way to speed up digestion and burn calories Boschmann, M, Steiniger, J, Hille, U, et al Franz-Volhard Clinical Research Center and Helios-Klinikum-Berlin, Medical Faculty of the Charité, Berlin, Germany. The Journal of Clinical Endocrinology & Metabolism, 2003 Dec;88(12):6015-9.. We may need more than those recommended eight glasses a day too. Now if only wine could speed metabolism...

7. Spice things up

The next time a chicken breast is cooking up in the kitchen, add a dash of cayenne pepper. The heat from the pepper is thanks to which wont only add a fiery kick—it could help boost metabolism, too Reinbach, H.C., Smeets, A, Martinussen, T. Department of Food Science, University of Copenhagen, Denmark. Clinical Nutrition, 2009 Jun;28(3):260-5. Epub 2009 Apr 3..

8. Squeeze in some cardio

Hop on the bike and clock in some miles—one study found that 45 minutes on the bike sped up metabolic rate for over 12 hours Knab, A.M., Shanely, R.A., Corbin, K.D., et al. Human Performance Laboratory, Appalachian State University, Kannapolis, NC. Medicine & Science in Sports & Exercise, 2011 Sep;43(9):1643-8.. Guess learning to ride a bike way back when was worth it!

9. Eat wisely

Who knew eating could actually help speed calorie burn? Certain foods like tuna and grapefruit have been shown to speed up metabolic rate Yamashita, Y, Yabu, T, Yamashita, M. Department of Veterinary Medicine, College of Bioresource Sciences, Nihon University, Fujisawa, Japan. The World Journal of Biological Chemistry, 2010 May 26; 1(5): 144–150. Murase, T, Misawa, K, Haramizu, S, et al. Biological Science Laboratories, Tochigi, Japan. American Journal of Physiology – Endocrinology and Metabolism, 2010 Aug;299(2):E266-75. Epub 2010 May 25.. has also shown to boost metabolism, so pick some eggs over pancakes at the breakfast table for a morning metabolism boost Bray, G.A., Smith, S.R., de Jonge, L, el a. Pennington Biomedical Research Center, Baton Rouge, LA. The Journal of the American Medical Association, 2012 Jan 4;307(1):47-55..

10. Grab a cup of Joe

This caffeinated morning beverage is not only a savior when it comes to pushing through a midterm paper or work meeting. A cup of coffee (or the in it) is absorbed into the blood stream very quickly, speeding up heart rate and provide a metabolic boost that peaks at about three hours after drinking Acheson, K.J., Zahorka-Markjewicz, B, Pittet, P, et al. The American Journal of Clinical Nutrition, 1980 May;33(5):989-97. Fredholm, B.B., Bättig, K., Holmén, J., et al. Section of Molecular Neuropharmacology, Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden. Pharmacological Reviews, 1999 Mar;51(1):83-133..

11. Laugh a lot!

A little laughter may go a long way. Scientists have found that as little as 10 minutes of laughter per day (or roughly half an episode of ) can burn energy Buchowski, M.S.m Majchrzak, K.M., Blomquist, K, et al. Department of Medicine, Vanderbilt University, Nashville, TN. International Journal of Obesity (London), 2007 Jan;31(1):131-7. Epub 2006 May 2.. Just another reason to stay smiling!

Originally posted January 2012. Updated December 2014.

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