You probably know people who eat terrible, don’t exercise and somehow still manage to be skinny. Research is begging to strengthen the idea of “skinny fat.” People who look skinny, but are metabolically obese: they suffer from high cholesterol, high blood pressure and type 2 diabetes. Unfortunately, this is no rare phenomenon. A JAMA study found than 1 in 4 “healthy” BMIs are actually “skinny fat”.
The Dangers of Being Skinny Fat:
How can a person be skinny and fat at the same time? As it turns out, there are two main types of fat: subcutaneous and visceral. Subcutaneous fat is the very visible fat that lies just beneath the skin. Visceral fat is located deep in your abdomen around your organs. In most people about 90% of fat is subcutaneous and 10% is visceral. However, a hallmark of the skinny fat is having a disproportionate amount of visceral fat. Unfortunately for the skinny fat, visceral fat is the worst kind. Studies have shown that visceral fat increases blood pressure, blood sugar, triglycerides, and lowers the levels of HDL (good) cholesterol to a greater degree than subcutaneous fat. Visceral fat also increases the risk of cardiovascular disease, type 2 diabetes, dementia, asthma, breast cancer and colorectal cancer disproportionately.
Perhaps not surprisingly then, studies have shown that skinny fat people actually have a higher risk of death than their obese peers.
What to Do About It:
Fortunately, you can quickly lose visceral fat through diet and exercise. One study had participants exercise between 15 and 20 hours a week. One group lifted at 70% of their max and ran at 30% of their max heart rate (Re). Another group lifted at 30% of their max and ran at 70% of their max heart rate (rE). The final group lifted and ran at 30% of their max (re). The researchers found that all groups lost visceral fat, but the groups that included higher intensity running or lifting experienced more visceral fat loss. See below:
So, this study shows that both cardio and strength training is beneficial and that higher intensities appear to work better. Another study found that a high volume exercise program (jogging 20 miles per week) reduced visceral fat more than a low volume program (jogging 12 miles a week). Another study had participants either do 4 bouts of 4 minutes of sprinting at 85% to 95% of max heart rate or run for 33 minutes at 60% to 70% of max heart rate. The researchers found that total body fat loss was similar in both groups, but only the high intensity group lost a significant amount of visceral fat.
In terms of diet, a study found that drinking a liter a day of cola for 6 months, led to 24% greater visceral fat than drinking a liter a day of water. Another study found that replacing saturated fat with polyunsaturated fat reduced visceral fat.
Even if you’re skinny, you could still be metabolically obese. A clear indicator of being “skinny fat” is having extra fat around your waist line. If this sounds like you, exercise at a high volume and intensity, avoid sugar, saturated fat, stress and be sure to get enough sleep.
Either way, these studies show the importance of living a healthy lifestyle no matter what the scale reads!
Chaput, Jean‐Philippe, Claude Bouchard, and Angelo Tremblay. “Change in sleep duration and visceral fat accumulation over 6 years in adults.” Obesity22.5 (2014): E9-E12.
Daubenmier, Jennifer, et al. “Mindfulness intervention for stress eating to reduce cortisol and abdominal fat among overweight and obese women: an exploratory randomized controlled study.” Journal of obesity 2011 (2011).
Dutheil, Frédéric, et al. “Different modalities of exercise to reduce visceral fat mass and cardiovascular risk in metabolic syndrome: the RESOLVE* randomized trial.” International journal of cardiology 168.4 (2013): 3634-3642.
Maersk, Maria, et al. “Sucrose-sweetened beverages increase fat storage in the liver, muscle, and visceral fat depot: a 6-mo randomized intervention study.” The American journal of clinical nutrition 95.2 (2012): 283-289.
Oliveros, Estefania, et al. “The concept of normal weight obesity.” Progress in cardiovascular diseases 56.4 (2014): 426-433.
Slentz, Cris A., et al. “Inactivity, exercise, and visceral fat. STRRIDE: a randomized, controlled study of exercise intensity and amount.” Journal of Applied Physiology 99.4 (2005): 1613-1618.
Summers, L. K. M., et al. “Substituting dietary saturated fat with polyunsaturated fat changes abdominal fat distribution and improves insulin sensitivity.” Diabetologia 45.3 (2002): 369-377.
Zhang, Haifeng, et al. “Effect of high-intensity interval training protocol on abdominal fat reduction in overweight Chinese women: A randomized controlled trial.” Kineziologija 47.1 (2015): 57-66.