Eliminating Visceral Fat

Visceral Adipose Tissue (aka visceral fat) is important to understand due to its tight association with metabolic disease.  Unfortunately, the presence of visceral fat is not always easy to detect and is certainly not discussed in ordinary health care interactions.

Consistent with the observation that visceral fat is associated with nearly all chronic metabolic disease processes, reduction of visceral fat is associated with improved metabolic markers – glucose regulation, blood pressure, etc..  Reduction of subcutaneous fat shows much less improvement in these markers of metabolic health.  In fact, in individuals with visceral obesity, there is a substantial improvement in metabolic health following a loss of a small amount of visceral fat.

 

Nutrition

Dietary interventions almost universally result in increased visceral fat loss relative to subcutaneous fat, reducing visceral fat by a greater percentage than the reduction in total body fat.

It appears that the body preferentially disposes of visceral fat when able to, perhaps reflecting that visceral fat stores are intended for temporary energy storage to be utilized in times of limited food intake.  In contrast, it can be more difficult to reduce subcutaneous fat stores.

While many of the studies referenced for these dietary interventions employ calorie restriction, it may be that the real benefit of these “diets” is due to the reduction of certain factors, specifically the nutrients that comprise processed foods:

• Sugars
• Refined carbohydrates
• Seed oils

In addition, alcohol is associated with the development of visceral fat, hence the oft-used term “beer belly”.

Carbohydrate restriction is more effective than low-fat diets at reducing truncal body fat, and there is robust evidence for carbohydrate restriction in reducing liver fat, as in NAFLD.

Increased protein intake (1.3 g/kg/day compared to 0.8 g/kg/day) in men over age 65 was associated with greater reduction in visceral fat.  Additionally, protein supplementation has favorable impact on visceral fat reduction.

 

Sleep

Sleep is consistently recognized as an important factor in overall health, including visceral fat accumulation.  Sleep deprivation causes an increase in the stress hormone cortisol which has myriad effects on metabolism.

 

Medications

There are numerous medications available for weight loss, but the GLP-1 agonists have shown the most success in reduction of overall fat and visceral fat.  They work through numerous mechanisms including improving the insulin sensitivity of fat tissue.  One such drug that is still in clinical trials, Beinaglutide, reduced visceral fat by 25% over 12 weeks.  Liraglutide, the first GLP-1 agonist to be approved for weight loss, reduces visceral fat including liver fat and  epicardial (heart) fat.

 

Exercise

Exercise has more of an impact on visceral fat reduction than does pharmacologic treatments.

One problem with interpreting studies on physical activity is that there is significant variation in protocols and definitions of what constitutes a particular form of activity.

Moderate aerobic exercise and high-intensity interval training (HIIT) both appear beneficial at reducing visceral fat.  Another study demonstrated that High-intensity exercise appears more beneficial than aerobic exercise.  In a group of moderately obese individuals, a pattern of high-resistance exercise proved more effective at visceral fat reduction than moderate-resistance exercise, independent of aerobic activity.

Note that, despite marketing claims that you might encounter, one cannot spot-reduce body fat.  Thus, performing exercises that isolate the abdominal musculature such as sit-ups or leg raises do not specifically reduce visceral fat.

HIIT and Sprint Interval Training (SIT) appear to have similar benefits in reducing VAT.  In this study, HIIT involved cycling at 90% of VO2 max for 4-minute bouts, followed by 3-minute passive recovery periods, while SIT involved maximal-intensity 6-second intervals of cycling followed by 9-second passive recovery periods.

Summary

In essence, the same behaviors that drive fat loss in general are also helpful for reducing visceral fat.  There are, however, some interventions that are particularly effective for targeting visceral fat.