In just 29 days, I dropped 13.0 pounds of fat. My waist shrunk from a soft and bloated 34 inches down to a rock-hard 30.75 inches. I added lean muscle. I got stronger every week. And I got 6 — check that — 8 pack abs just in time for a beach vacation.
Ask any personal trainer, nutritionist, dietician, doctor or "Fitness Guru" and they will all give you the same tired, conventional wisdom:
I’m a certified personal trainer and founder of Fitness Under Oath. As the name states, I’ve made a career out of revealing the TRUTH about all things fitness.
Until just recently, I too thought it was better to lose fat slowly. After all, that’s what "everybody" says, right?
I started looking at the clinical research of rapid fat loss versus the science of slow and steady fat loss. And what I discovered SHOCKED me. Because despite what I’d always heard, it turns out..
I know this sounds unbelievable. I know this flies in the face of what you’ve always been told. But the science backs me up. See for yourself:
Scientists from Newcastle University put this common misconception to the test. They took 3 groups of over overweight men and put them on a diet.
All groups ended up losing approximately 5% of their bodyweight. The difference is how long it took. Group 1 did it in 6 days. Group two did it in 3 weeks. Group 3 did it in 6 weeks.
Siervo, Mario, et al. "Imposed rate and extent of weight loss in obese men and adaptive changes in resting and total energy expenditure." Metabolism (2015): Accepted Article.
Researchers took a group of mice and put them on a 5% caloric restricted diet. This means they ate 5% fewer calories than usual. This is the very definition of a "slow & steady" diet. The opposite of a crash diet.
So clearly trying to lose weight with a mild (5%) caloric deficit is a recipe for disaster if you are a rat. But humans are different right? Check out the next drop down box (Bad for your hormones) to see why slow and steady fat loss is a bad idea for us humans too…
Li X, Cope MB, Johnson MS, Smith DL Jr, Nagy TR. Mild calorie restriction induces fat accumulation in female C57BL/6J mice. Obesity (Silver Spring). 2010 Mar;18(3):456-62.
Ever heard the idea that you should lose fat slowly because if you lose fat too fast it will screw up your hormones? Turns that’s really an old wives tale. Here’s the truth: A human study examining the effects of long-term mild-caloric deficit dieting in humans found that long-term dieters suffered from 78% lower testosterone levels and 28% lower VO2Max levels! The research is clear: Slow & steady dieting is WORSE for your hormones.
Fontana L, Klein S, Holloszy JO. Effects of long-term calorie restriction and endurance exercise on glucose tolerance, insulin action, and adipokine production. Age (Dordr). 2010 Mar;32(1):97-108.
I know this is surprising because we’ve always been told that "crash" dieting leads to "yo-yo" weight gain. But science paints a different picture:
A long-term analysis of European dieters showed that dieters who lost the most weight during an initial 8-week diet phase were the most successful at KEEPING the weight off six months later. This principle held true even when the dieters were using a very low-calorie approach (less than 800 calories a day) during their initial weight loss phase. Scientifically-validated research proves that if you want to lose weight AND KEEP IT OFF, you should lose the weight FAST.
Wong MHT, Holst C, Astrup A, Handjieva-Darlenska T, Jebb SA. Caloric Restriction Induces Changes in Insulin and Body Weight Measurements That Are Inversely Associated with Subsequent Weight Regain. PLoS ONE. 2012; 7(8): e42858.
The research is clear. You should approach fat loss like a smash-and-grab bank robber: Get in, get the job done, and get right back to your normal life as fast and possible. In other words, don’t stay on a "diet" for a single minute longer than absolutely necessary. Now… Read more…