Overweight mice can slim down if you let them run daily on a treadmill. If you give them a garlic extract as well then they’ll lose even more fat. But how does garlic speed up weight loss? The researchers at Inje University in Korea didn’t manage to work that out.
If you are too fat, you’re in a state of continuous inflammation. Those layers of fat are literally rotting away, and your immune cells are busy clearing up the died-off fat cells. Added to that, inflammatory proteins like interleukin-6, tumor
necrosis factor-alpha and C-reactive protein are being released. These do all sorts of unhealthy things in your body, one of which is that they stimulate the growth of fat tissue.
Garlic enhances slimming effect of running
Garlic extracts contain compounds such as gamma-glutamylcysteine, S-allylcysteine [structural formula shown here], S-allylmercaptocysteine and S-methylcysteine. These inhibit the production of inflammatory factors, so you’d expect them to have an anti-obesity effect.
The Koreans decided to find out whether this is indeed the case. At the cost of the Korean government they fattened a group of lab rats for six weeks, using a high-fat diet [HFD] and gave a control group ordinary feed [ND]. After that the real experiment started, and continued for 4 weeks.
The Koreans let one group of rats continue to fatten [HFD] and gave another group 2.8 g Aged Garlic Extract per kg bodyweight every day [HFD+AGE]. The supplement was given orally. The extract came from the Uiseong Black-Garlic Farming Association of Korea, but as far as we can tell from reading the article this organisation did not fund the research.
Another group of rats had to run on a treadmill five days a week [HFD+Exercise]. The researchers gradually increased the intensity of the exercise each week.
A fourth and final group of rats had to run and were also given the garlic extract [HFD+Exercise+AGE]. They were given the extract half an hour before they were put on the treadmill.
The figure and table below show that garlic and exercise mutually reinforced each other’s slimming effect. Click on the table for a larger version.
The table above shows that the rats in the HFD+Exercise+AGE group started to eat less. But that doesn’t explain why the animals in this group lost weight more quickly than the animals in the HFD+Exercise group. The food-efficiency ratio decreased as a result of the combination of running and garlic supplementation. That means that the rats grew less with the same amount of food.
How that happened the Koreans don’t understand, as their theory didn’t hold water. They observed no effect of the garlic extract on the inflammatory proteins mentioned above. The concentration of triglycerides in the blood of the rats in the HFD+Exercise+AGE group declined considerably. Apparently the combination of a garlic supplement and exercise does something to fat metabolism. We hazard a guess, in one word: UCPs.
“Aged Garlic Extract with exercise is more effective in controlling obesity than either intervention alone”, the Koreans write. “However, more extensive research is needed before recommending Aged Garlic Extract supplementation to obese humans.”
Aged garlic extract enhances exercise-mediated improvement of metabolic parameters in high fat diet-induced obese rats.
Seo DY, Lee S, Figueroa A, Kwak YS, Kim N, Rhee BD, Ko KS, Bang HS, Baek YH, Han J.
National Research Laboratory for Mitochondrial Signaling, Department of Physiology, College of Medicine, Cardiovascular and Metabolic Disease Center, Inje University, 633-165, Gaegeum-dong, Busanjin-gu, Busan 614-735, Korea.
Aged garlic extract (AGE) is known to have a protective effect against immune system, endothelial function, oxidative stress and inflammation. We examined the effects of exercise with and without aged garlic extract administration on body weight, lipid profiles, inflammatory cytokines, and oxidative stress marker in high-fat diet (HFD)-induced obese rats. Forty-five Sprague-Dawley rats were fed either a HFD (HFD, n = 40) or a normal diet (ND, n = 5) for 6 weeks and thereafter randomized into ND (n = 5), HFD (n = 10), HFD with AGE (n = 10), HFD with Exercise (n = 10), or HFD with Exercise+AGE (n = 10) for 4 weeks. AGE groups were administered at a dose of 2.86 g/kg·body weight, orally. Exercise consisted of running 15-60 min 5 days/week with gradually increasing intensity. AGE (P < 0.01), Exercise, and Exercise+AGE (P < 0.001) attenuated body weight gain and food efficiency ratio compared to HFD. Visceral fat and liver weight gain were attenuated (P < 0.05) with all three interventions with a greater effect on visceral fat in the Exercise+AGE than AGE (P < 0.001). In reducing visceral fat (P < 0.001), epididymal fat (P < 0.01) and liver weight (P < 0.001), Exercise+AGE was effective, but exercise showed a stronger suppressive effect than AGE. Exercise+AGE showed further additive effects on reducing visceral fat and liver weight (P < 0.001). AGE significantly attenuated the increase in total cholesterol and low-density lipoprotein-cholesterol compared with HFD (P < 0.05). Exercise+AGE attenuated the increase in triglycerides compared with HFD (P < 0.05). Exercise group significantly decrease in C-reactive protein (P < 0.001). These results suggest that AGE supplementation and exercise alone have anti-obesity, cholesterol lowering, and anti-inflammatory effects, but the combined intervention is more effective in reducing weight gain and triglycerides levels than either intervention alone.
PMID: 23346301 [PubMed] PMCID: PMC3542441