DAG: Does It Really Burn Fat?
DAG: Does It Really Burn Fat?
I hear people talking about which is the best fat for enhancing weight loss. I hear about olive oil, coconut oil, MCT oils, and macadamia nut oil— but the other day, I was in the grocery store, and next to the olive oil, I noticed a unique oil blend called ENOVA,® which is rich in diglycerides (DAG). DAG is a glyceride consisting of two fatty-acid chains covalently bonded to a glycerol molecule through ester linkages. Cooking and salad oils contain two types of fats, triglycerides (TAG) and DAG.
Common cooking oils, like vegetable and corn oil, are TAG-based, with small amounts of DAG. The bottle claims that by using this particular type of oil, which is rich in DAG, “metabolism of DAG can help you maintain healthy bodyweight and body fat.” Enova® brand oil, made from natural soy and canola oils, is the only DAG-rich oil on the market, and it’s supported by more than 20 years of scientific research. Studies show that consumption of DAG-rich oil results in lower serum triglyceride levels after a meal. And the metabolism of DAG can help you maintain healthy bodyweight and body fat.
The Science Behind DAG
DAG molecules follow a similar path as triglycerides; however, the majority of the DAG molecules can’t be efficiently reassembled into chylomicrons by enzymes in the small intestine. That’s because chylomicrons transport exogenous lipids to liver, adipose, cardiac and skeletal muscle tissue where their triglyceride components are unloaded by the activity of lipoprotein lipase. As a result, they travel through the portal system to the liver where they’re oxidized, and less is available to be stored as fat.
DAG oil affects both bodyweight and body fat in humans and animals.1-4 The factors involved in controlling bodyweight and body fat include increased energy expenditure, fat oxidation, fat storage capacity, and appetite control.5 Increasing fat for use as energy is an evolving concept as a way to maintain fat balance (fat intake minus fat oxidation) and energy balance (energy intake minus energy expenditure).6
Several recent studies have examined the effects of DAG oil on energy metabolism. It has been suggested that the position of the fatty acid on the glycerol skeleton is responsible for the metabolic differences of DAG oil. It is hypothesized that the DAG is less readily resynthesized as chylomicrons and is directly transported to the portal vein for oxidation. This increase in fat oxidation may lead to increased satiety. Specifically, DAG, in contrast to dietary TAG, has been associated with positive physiological outcomes in the area of weight control, fat deposition, and lipid metabolism. Thus, a new strategy proposed to prevent weight gain and fat deposition is the inclusion of DAG-enriched oil in the diet.
Human Studies With DAG
Several short-term human studies demonstrated greater fat oxidation with DAG oil consumption for a single meal,7 for one day,8 and four days,9 compared with TAG oil consumption. A previous study observed that DAG oil consumption increased fat oxidation levels in humans, although it did not affect energy expenditure over a 36-hour stay in a respiratory chamber.8 The magnitude of the increase in fat oxidation in this study was 4 grams per day, equivalent to approximately 1,460 grams per year.
The researchers suggested that an increase in fat oxidation may enhance weight loss over the long term. The enhanced fat utilization associated with DAG oil consumption may suppress body fat accumulation and body fat gain by altering the fat balance. The mechanism by which DAG oil increases fat oxidation remains speculative.
Insulin is the most potent regulator of postprandial fat metabolism through the mediation of lipoprotein lipase and hormone-sensitive lipase (a fat storage enzyme). Two studies have reported lower postprandial insulin levels after loading with a diet containing DAG oil, compared with a diet containing TAG oil.7,10 The lower postprandial insulin levels after DAG oil consumption compared with TAG oil consumption indicated a smaller stimulus in the direction of fat storage, and increased postprandial fat utilization may be associated with the findings of increased total fat utilization in DAG oil consumption.
The results from animal and human studies indicate that dietary DAG has a faster oxidation rate than dietary TAG, and that DAG oil consumption increases whole-body fat oxidation, compared with TAG oil. The mechanism of enhanced fat utilization following DAG oil consumption may be related to the lower postprandial insulin levels compared to those after TAG oil consumption. Enhanced energy metabolism may explain the greater loss of bodyweight and body fat in overweight and obese individuals who consume a DAG oil diet.
1. Maki KC, Davidson MH, Tsushima R, Matsuo N, Tokimitsu I, Umporowicz DM, Dicklin MR, Foster GS, Ingram KA, Anderson BD, Frost SD, and Bell M. (2002) Consumption of diacylglycerol oil as part of a reduced-energy diet enhances loss of bodyweight and fat in comparison with consumption of a triacylglycerol control oil. Am J Clin Nutr, 76, 1230-1236.
2. Nagao T, Watanabe H, Goto N, Onizawa K, Taguchi H, Matsuo N, Yasukawa T, Tsushima R, Shimasaki H, and Itakura H. (2000) Dietary diacylglycerol suppresses accumulation of body fat compared to triacylglycerol in men in a double-blind controlled trial. J Nutr, 130, 792-797.
3. Kawashima H, Takase H, Yasunaga K, Wakaki Y, Katsuragi Y, Mori K, Yamaguchi T, Hase T, Matsuo N, Yasukawa T, Tokimitsu I, and Koyama W. (2008) One-year ad libitum consumption of diacylglycerol oil as part of a regular diet results in modest weight loss in comparison with consumption of a triacylglycerol control oil in overweight Japanese subjects. J Am Diet Assoc, 108, 57-66.
4. Murase T, Mizuno T, Omachi T, Onizawa K, Komine Y, Kondo H, Hase T, and Tokimitsu I. (2001) Dietary diacylglycerol suppresses high fat and high sucrose diet-induced body fat accumulation in C57BL/6J mice. J Lipid Res, 42, 372-378.
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7. Saito S, Tomonobu K, Hase T, and Tokimitsu I. (2005) Effects of diacylglycerol on postprandial energy expenditure and respiratory quotient in healthy subjects. Nutrition, 22, 30-35.
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