The relationship between Zinc and Obesity is moderately strong. Zinc ranks 31 of 873 Obesity treatments on our list.

Obesity is a medical condition in which excess body fat has accumulated to the extent that it may have a negative effect on health, leading to reduced life expectancy and/or increased health problems. People are considered obese when their body mass index (BMI), a measurement obtained by dividing a person's weight by the square of the person's height, exceeds 30 kg/m.

Zinc, in commerce also spelter, is a metallic chemical element; it has the symbol Zn and atomic number 30. It is the first element of group 12 of the periodic table. In some respects zinc is chemically similar to magnesium: its ion is of similar size and its only common oxidation state is +2. Zinc is the 24th most abundant element in the Earth's crust and has five stable isotopes. The most common zinc ore is sphalerite (zinc blende), a zinc sulfide mineral. The largest mineable amounts are found in Australia, Asia, and the United States. Zinc production includes froth flotation of the ore, roasting, and final extraction using electricity (electrowinning).

Researchers have concluded:

  • Besides lifestyle modification, zinc supplementation might be considered as a useful and safe additional intervention treatment for improvement of cardiometabolic risk factors related to childhood obesity.1
  • ZAG could be involved in modulating lipid metabolism in adipose tissue and is associated with insulin resistance. These findings suggest that ZAG may be a useful target in obesity and related disorders, such as diabetes.2
  • Zinc increased the leptin concentrations in obese individuals, but did not modify insulin sensitivity and androgens.3
  • In obese patients, a single-day stress/rest low-dose ultrafast protocol with a CZT camera is clinically feasible and provides high image quality.4
  • Patients with BMI ≥ 40 kg/m(2) should be scheduled for myocardial perfusion imaging on a conventional SPECT camera, as it is difficult to obtain diagnostic image quality on a cadmium-zinc-telluride camera.5

Review all research »

Strength of evidence

Zinc for Obesity ranks in the top 67% of condition-treatment relationships we analyzed.

Importantly, we found 18 studies that were randomized and controlled. Such studies are considered the most rigorous, and help to establish or disprove a cause-and-effect relationship between prospective treatments and conditions. So there may be some good evidence on which to make a decision about using Zinc for Obesity.

Amount of research

The relationship between Obesity and Zinc has been somewhat well researched. We found 475 relevant research articles on the topic. This places the volume of research in the top 58% of condition-treatment relationships we analyzed.

Research trends

Are researchers becoming more or less interested in Zinc for Obesity? The pace of research appears to be increasing:

Important caveat—help improve this information

Please note that our analysis is automated and imperfect. If you have personal insight, please help improve our analysis by rating this relationship and the research supporting it. And check back regularly; we last analyzed research for this relationship on Jul 20, 2014, and are constantly updating our database and algorithms.


Other names
Zinc for Obesity is also known as Element 30 for Adipositas, Element 30 for Adult Obesity, Element 30 for Boddy wieght problem, Element 30 for Clinical obesity, Element 30 for Clinically obese, Element 30 for Clinically severe obesity, Element 30 for Corpulence, Element 30 for Corpulent, Element 30 for Dunlap disease, Element 30 for Effects of obesity on health, Element 30 for Environmental causes of obesity, Element 30 for Exogenous obesity, Element 30 for Fat dude, Element 30 for Fat Guy, Element 30 for Fat people, Element 30 for Fat person, Element 30 for Flabbiness, Element 30 for Genetics and obesity, Element 30 for Morbid obesity, Element 30 for Morbidly obese, Element 30 for Morbidogenic, Element 30 for Obeast, Element 30 for Obecity, Element 30 for Obese, Element 30 for Obesity, morbid, Element 30 for Obesityness, Element 30 for Obseity, Element 30 for Overobeseness, Element 30 for Overobesity, Element 30 for Severe obesity, Element 30 for Super obese, Element 30 for Truncal obesity, Element 30 for Weight problem, Mossy zinc for Adipositas, Mossy zinc for Adult Obesity, Mossy zinc for Boddy wieght problem, Mossy zinc for Clinical obesity, Mossy zinc for Clinically obese, Mossy zinc for Clinically severe obesity, Mossy zinc for Corpulence, Mossy zinc for Corpulent, Mossy zinc for Dunlap disease, Mossy zinc for Effects of obesity on health, Mossy zinc for Environmental causes of obesity, Mossy zinc for Exogenous obesity, Mossy zinc for Fat dude, Mossy zinc for Fat Guy, Mossy zinc for Fat people, Mossy zinc for Fat person, Mossy zinc for Flabbiness, Mossy zinc for Genetics and obesity, Mossy zinc for Morbid obesity, Mossy zinc for Morbidly obese, Mossy zinc for Morbidogenic, Mossy zinc for Obeast, Mossy zinc for Obecity, Mossy zinc for Obese, Mossy zinc for Obesity, morbid, Mossy zinc for Obesityness, Mossy zinc for Obseity, Mossy zinc for Overobeseness, Mossy zinc for Overobesity, Mossy zinc for Severe obesity, Mossy zinc for Super obese, Mossy zinc for Truncal obesity, Mossy zinc for Weight problem, SHG zinc for Adipositas, SHG zinc for Adult Obesity, SHG zinc for Boddy wieght problem, SHG zinc for Clinical obesity, SHG zinc for Clinically obese, SHG zinc for Clinically severe obesity, SHG zinc for Corpulence, SHG zinc for Corpulent, SHG zinc for Dunlap disease, SHG zinc for Effects of obesity on health, SHG zinc for Environmental causes of obesity, SHG zinc for Exogenous obesity, SHG zinc for Fat dude, SHG zinc for Fat Guy, SHG zinc for Fat people, SHG zinc for Fat person, SHG zinc for Flabbiness, SHG zinc for Genetics and obesity, SHG zinc for Morbid obesity, SHG zinc for Morbidly obese, SHG zinc for Morbidogenic, SHG zinc for Obeast, SHG zinc for Obecity, SHG zinc for Obese, SHG zinc for Obesity, morbid, SHG zinc for Obesityness, SHG zinc for Obseity, SHG zinc for Overobeseness, SHG zinc for Overobesity, SHG zinc for Severe obesity, SHG zinc for Super obese, SHG zinc for Truncal obesity, SHG zinc for Weight problem, Special high grade zinc for Adipositas, Special high grade zinc for Adult Obesity, Special high grade zinc for Boddy wieght problem, Special high grade zinc for Clinical obesity, Special high grade zinc for Clinically obese, Special high grade zinc for Clinically severe obesity, Special high grade zinc for Corpulence, Special high grade zinc for Corpulent, Special high grade zinc for Dunlap disease, Special high grade zinc for Effects of obesity on health, Special high grade zinc for Environmental causes of obesity, Special high grade zinc for Exogenous obesity, Special high grade zinc for Fat dude, Special high grade zinc for Fat Guy, Special high grade zinc for Fat people, Special high grade zinc for Fat person, Special high grade zinc for Flabbiness, Special high grade zinc for Genetics and obesity, Special high grade zinc for Morbid obesity, Special high grade zinc for Morbidly obese, Special high grade zinc for Morbidogenic, Special high grade zinc for Obeast, Special high grade zinc for Obecity, Special high grade zinc for Obese, Special high grade zinc for Obesity, morbid, Special high grade zinc for Obesityness, Special high grade zinc for Obseity, Special high grade zinc for Overobeseness, Special high grade zinc for Overobesity, Special high grade zinc for Severe obesity, Special high grade zinc for Super obese, Special high grade zinc for Truncal obesity, Special high grade zinc for Weight problem, Super high grade zinc for Adipositas, Super high grade zinc for Adult Obesity, Super high grade zinc for Boddy wieght problem, Super high grade zinc for Clinical obesity, Super high grade zinc for Clinically obese, Super high grade zinc for Clinically severe obesity, Super high grade zinc for Corpulence, Super high grade zinc for Corpulent, Super high grade zinc for Dunlap disease, Super high grade zinc for Effects of obesity on health, Super high grade zinc for Environmental causes of obesity, Super high grade zinc for Exogenous obesity, Super high grade zinc for Fat dude, Super high grade zinc for Fat Guy, Super high grade zinc for Fat people, Super high grade zinc for Fat person, Super high grade zinc for Flabbiness, Super high grade zinc for Genetics and obesity, Super high grade zinc for Morbid obesity, Super high grade zinc for Morbidly obese, Super high grade zinc for Morbidogenic, Super high grade zinc for Obeast, Super high grade zinc for Obecity, Super high grade zinc for Obese, Super high grade zinc for Obesity, morbid, Super high grade zinc for Obesityness, Super high grade zinc for Obseity, Super high grade zinc for Overobeseness, Super high grade zinc for Overobesity, Super high grade zinc for Severe obesity, Super high grade zinc for Super obese, Super high grade zinc for Truncal obesity, Super high grade zinc for Weight problem, Zinc (element) for Adipositas, Zinc (element) for Adult Obesity, Zinc (element) for Boddy wieght problem, Zinc (element) for Clinical obesity, Zinc (element) for Clinically obese, Zinc (element) for Clinically severe obesity, Zinc (element) for Corpulence, Zinc (element) for Corpulent, Zinc (element) for Dunlap disease, Zinc (element) for Effects of obesity on health, Zinc (element) for Environmental causes of obesity, Zinc (element) for Exogenous obesity, Zinc (element) for Fat dude, Zinc (element) for Fat Guy, Zinc (element) for Fat people, Zinc (element) for Fat person, Zinc (element) for Flabbiness, Zinc (element) for Genetics and obesity, Zinc (element) for Morbid obesity, Zinc (element) for Morbidly obese, Zinc (element) for Morbidogenic, Zinc (element) for Obeast, Zinc (element) for Obecity, Zinc (element) for Obese, Zinc (element) for Obesity, morbid, Zinc (element) for Obesityness, Zinc (element) for Obseity, Zinc (element) for Overobeseness, Zinc (element) for Overobesity, Zinc (element) for Severe obesity, Zinc (element) for Super obese, Zinc (element) for Truncal obesity, Zinc (element) for Weight problem, Zinc alloy for Adipositas, Zinc alloy for Adult Obesity, Zinc alloy for Boddy wieght problem, Zinc alloy for Clinical obesity, Zinc alloy for Clinically obese, Zinc alloy for Clinically severe obesity, Zinc alloy for Corpulence, Zinc alloy for Corpulent, Zinc alloy for Dunlap disease, Zinc alloy for Effects of obesity on health, Zinc alloy for Environmental causes of obesity, Zinc alloy for Exogenous obesity, Zinc alloy for Fat dude, Zinc alloy for Fat Guy, Zinc alloy for Fat people, Zinc alloy for Fat person, Zinc alloy for Flabbiness, Zinc alloy for Genetics and obesity, Zinc alloy for Morbid obesity, Zinc alloy for Morbidly obese, Zinc alloy for Morbidogenic, Zinc alloy for Obeast, Zinc alloy for Obecity, Zinc alloy for Obese, Zinc alloy for Obesity, morbid, Zinc alloy for Obesityness, Zinc alloy for Obseity, Zinc alloy for Overobeseness, Zinc alloy for Overobesity, Zinc alloy for Severe obesity, Zinc alloy for Super obese, Zinc alloy for Truncal obesity, Zinc alloy for Weight problem, Zinc alloys for Adipositas, Zinc alloys for Adult Obesity, Zinc alloys for Boddy wieght problem, Zinc alloys for Clinical obesity, Zinc alloys for Clinically obese, Zinc alloys for Clinically severe obesity, Zinc alloys for Corpulence, Zinc alloys for Corpulent, Zinc alloys for Dunlap disease, Zinc alloys for Effects of obesity on health, Zinc alloys for Environmental causes of obesity, Zinc alloys for Exogenous obesity, Zinc alloys for Fat dude, Zinc alloys for Fat Guy, Zinc alloys for Fat people, Zinc alloys for Fat person, Zinc alloys for Flabbiness, Zinc alloys for Genetics and obesity, Zinc alloys for Morbid obesity, Zinc alloys for Morbidly obese, Zinc alloys for Morbidogenic, Zinc alloys for Obeast, Zinc alloys for Obecity, Zinc alloys for Obese, Zinc alloys for Obesity, morbid, Zinc alloys for Obesityness, Zinc alloys for Obseity, Zinc alloys for Overobeseness, Zinc alloys for Overobesity, Zinc alloys for Severe obesity, Zinc alloys for Super obese, Zinc alloys for Truncal obesity, Zinc alloys for Weight problem, Zinc ions for Adipositas, Zinc ions for Adult Obesity, Zinc ions for Boddy wieght problem, Zinc ions for Clinical obesity, Zinc ions for Clinically obese, Zinc ions for Clinically severe obesity, Zinc ions for Corpulence, Zinc ions for Corpulent, Zinc ions for Dunlap disease, Zinc ions for Effects of obesity on health, Zinc ions for Environmental causes of obesity, Zinc ions for Exogenous obesity, Zinc ions for Fat dude, Zinc ions for Fat Guy, Zinc ions for Fat people, Zinc ions for Fat person, Zinc ions for Flabbiness, Zinc ions for Genetics and obesity, Zinc ions for Morbid obesity, Zinc ions for Morbidly obese, Zinc ions for Morbidogenic, Zinc ions for Obeast, Zinc ions for Obecity, Zinc ions for Obese, Zinc ions for Obesity, morbid, Zinc ions for Obesityness, Zinc ions for Obseity, Zinc ions for Overobeseness, Zinc ions for Overobesity, Zinc ions for Severe obesity, Zinc ions for Super obese, Zinc ions for Truncal obesity, Zinc ions for Weight problem, Zinc metabolism for Adipositas, Zinc metabolism for Adult Obesity, Zinc metabolism for Boddy wieght problem, Zinc metabolism for Clinical obesity, Zinc metabolism for Clinically obese, Zinc metabolism for Clinically severe obesity, Zinc metabolism for Corpulence, Zinc metabolism for Corpulent, Zinc metabolism for Dunlap disease, Zinc metabolism for Effects of obesity on health, Zinc metabolism for Environmental causes of obesity, Zinc metabolism for Exogenous obesity, Zinc metabolism for Fat dude, Zinc metabolism for Fat Guy, Zinc metabolism for Fat people, Zinc metabolism for Fat person, Zinc metabolism for Flabbiness, Zinc metabolism for Genetics and obesity, Zinc metabolism for Morbid obesity, Zinc metabolism for Morbidly obese, Zinc metabolism for Morbidogenic, Zinc metabolism for Obeast, Zinc metabolism for Obecity, Zinc metabolism for Obese, Zinc metabolism for Obesity, morbid, Zinc metabolism for Obesityness, Zinc metabolism for Obseity, Zinc metabolism for Overobeseness, Zinc metabolism for Overobesity, Zinc metabolism for Severe obesity, Zinc metabolism for Super obese, Zinc metabolism for Truncal obesity, Zinc metabolism for Weight problem, Zinc metallurgy for Adipositas, Zinc metallurgy for Adult Obesity, Zinc metallurgy for Boddy wieght problem, Zinc metallurgy for Clinical obesity, Zinc metallurgy for Clinically obese, Zinc metallurgy for Clinically severe obesity, Zinc metallurgy for Corpulence, Zinc metallurgy for Corpulent, Zinc metallurgy for Dunlap disease, Zinc metallurgy for Effects of obesity on health, Zinc metallurgy for Environmental causes of obesity, Zinc metallurgy for Exogenous obesity, Zinc metallurgy for Fat dude, Zinc metallurgy for Fat Guy, Zinc metallurgy for Fat people, Zinc metallurgy for Fat person, Zinc metallurgy for Flabbiness, Zinc metallurgy for Genetics and obesity, Zinc metallurgy for Morbid obesity, Zinc metallurgy for Morbidly obese, Zinc metallurgy for Morbidogenic, Zinc metallurgy for Obeast, Zinc metallurgy for Obecity, Zinc metallurgy for Obese, Zinc metallurgy for Obesity, morbid, Zinc metallurgy for Obesityness, Zinc metallurgy for Obseity, Zinc metallurgy for Overobeseness, Zinc metallurgy for Overobesity, Zinc metallurgy for Severe obesity, Zinc metallurgy for Super obese, Zinc metallurgy for Truncal obesity, Zinc metallurgy for Weight problem, Zinc pills for Adipositas, Zinc pills for Adult Obesity, Zinc pills for Boddy wieght problem, Zinc pills for Clinical obesity, Zinc pills for Clinically obese, Zinc pills for Clinically severe obesity, Zinc pills for Corpulence, Zinc pills for Corpulent, Zinc pills for Dunlap disease, Zinc pills for Effects of obesity on health, Zinc pills for Environmental causes of obesity, Zinc pills for Exogenous obesity, Zinc pills for Fat dude, Zinc pills for Fat Guy, Zinc pills for Fat people, Zinc pills for Fat person, Zinc pills for Flabbiness, Zinc pills for Genetics and obesity, Zinc pills for Morbid obesity, Zinc pills for Morbidly obese, Zinc pills for Morbidogenic, Zinc pills for Obeast, Zinc pills for Obecity, Zinc pills for Obese, Zinc pills for Obesity, morbid, Zinc pills for Obesityness, Zinc pills for Obseity, Zinc pills for Overobeseness, Zinc pills for Overobesity, Zinc pills for Severe obesity, Zinc pills for Super obese, Zinc pills for Truncal obesity, Zinc pills for Weight problem, Zinc poisoning for Adipositas, Zinc poisoning for Adult Obesity, Zinc poisoning for Boddy wieght problem, Zinc poisoning for Clinical obesity, Zinc poisoning for Clinically obese, Zinc poisoning for Clinically severe obesity, Zinc poisoning for Corpulence, Zinc poisoning for Corpulent, Zinc poisoning for Dunlap disease, Zinc poisoning for Effects of obesity on health, Zinc poisoning for Environmental causes of obesity, Zinc poisoning for Exogenous obesity, Zinc poisoning for Fat dude, Zinc poisoning for Fat Guy, Zinc poisoning for Fat people, Zinc poisoning for Fat person, Zinc poisoning for Flabbiness, Zinc poisoning for Genetics and obesity, Zinc poisoning for Morbid obesity, Zinc poisoning for Morbidly obese, Zinc poisoning for Morbidogenic, Zinc poisoning for Obeast, Zinc poisoning for Obecity, Zinc poisoning for Obese, Zinc poisoning for Obesity, morbid, Zinc poisoning for Obesityness, Zinc poisoning for Obseity, Zinc poisoning for Overobeseness, Zinc poisoning for Overobesity, Zinc poisoning for Severe obesity, Zinc poisoning for Super obese, Zinc poisoning for Truncal obesity, Zinc poisoning for Weight problem, Zinc Processing for Adipositas, Zinc Processing for Adult Obesity, Zinc Processing for Boddy wieght problem, Zinc Processing for Clinical obesity, Zinc Processing for Clinically obese, Zinc Processing for Clinically severe obesity, Zinc Processing for Corpulence, Zinc Processing for Corpulent, Zinc Processing for Dunlap disease, Zinc Processing for Effects of obesity on health, Zinc Processing for Environmental causes of obesity, Zinc Processing for Exogenous obesity, Zinc Processing for Fat dude, Zinc Processing for Fat Guy, Zinc Processing for Fat people, Zinc Processing for Fat person, Zinc Processing for Flabbiness, Zinc Processing for Genetics and obesity, Zinc Processing for Morbid obesity, Zinc Processing for Morbidly obese, Zinc Processing for Morbidogenic, Zinc Processing for Obeast, Zinc Processing for Obecity, Zinc Processing for Obese, Zinc Processing for Obesity, morbid, Zinc Processing for Obesityness, Zinc Processing for Obseity, Zinc Processing for Overobeseness, Zinc Processing for Overobesity, Zinc Processing for Severe obesity, Zinc Processing for Super obese, Zinc Processing for Truncal obesity, Zinc Processing for Weight problem, Zinc tablets for Adipositas, Zinc tablets for Adult Obesity, Zinc tablets for Boddy wieght problem, Zinc tablets for Clinical obesity, Zinc tablets for Clinically obese, Zinc tablets for Clinically severe obesity, Zinc tablets for Corpulence, Zinc tablets for Corpulent, Zinc tablets for Dunlap disease, Zinc tablets for Effects of obesity on health, Zinc tablets for Environmental causes of obesity, Zinc tablets for Exogenous obesity, Zinc tablets for Fat dude, Zinc tablets for Fat Guy, Zinc tablets for Fat people, Zinc tablets for Fat person, Zinc tablets for Flabbiness, Zinc tablets for Genetics and obesity, Zinc tablets for Morbid obesity, Zinc tablets for Morbidly obese, Zinc tablets for Morbidogenic, Zinc tablets for Obeast, Zinc tablets for Obecity, Zinc tablets for Obese, Zinc tablets for Obesity, morbid, Zinc tablets for Obesityness, Zinc tablets for Obseity, Zinc tablets for Overobeseness, Zinc tablets for Overobesity, Zinc tablets for Severe obesity, Zinc tablets for Super obese, Zinc tablets for Truncal obesity, Zinc tablets for Weight problem, Zinc tiles for Adipositas, Zinc tiles for Adult Obesity, Zinc tiles for Boddy wieght problem, Zinc tiles for Clinical obesity, Zinc tiles for Clinically obese, Zinc tiles for Clinically severe obesity, Zinc tiles for Corpulence, Zinc tiles for Corpulent, Zinc tiles for Dunlap disease, Zinc tiles for Effects of obesity on health, Zinc tiles for Environmental causes of obesity, Zinc tiles for Exogenous obesity, Zinc tiles for Fat dude, Zinc tiles for Fat Guy, Zinc tiles for Fat people, Zinc tiles for Fat person, Zinc tiles for Flabbiness, Zinc tiles for Genetics and obesity, Zinc tiles for Morbid obesity, Zinc tiles for Morbidly obese, Zinc tiles for Morbidogenic, Zinc tiles for Obeast, Zinc tiles for Obecity, Zinc tiles for Obese, Zinc tiles for Obesity, morbid, Zinc tiles for Obesityness, Zinc tiles for Obseity, Zinc tiles for Overobeseness, Zinc tiles for Overobesity, Zinc tiles for Severe obesity, Zinc tiles for Super obese, Zinc tiles for Truncal obesity, Zinc tiles for Weight problem, Zn2+ for Adipositas, Zn2+ for Adult Obesity, Zn2+ for Boddy wieght problem, Zn2+ for Clinical obesity, Zn2+ for Clinically obese, Zn2+ for Clinically severe obesity, Zn2+ for Corpulence, Zn2+ for Corpulent, Zn2+ for Dunlap disease, Zn2+ for Effects of obesity on health, Zn2+ for Environmental causes of obesity, Zn2+ for Exogenous obesity, Zn2+ for Fat dude, Zn2+ for Fat Guy, Zn2+ for Fat people, Zn2+ for Fat person, Zn2+ for Flabbiness, Zn2+ for Genetics and obesity, Zn2+ for Morbid obesity, Zn2+ for Morbidly obese, Zn2+ for Morbidogenic, Zn2+ for Obeast, Zn2+ for Obecity, Zn2+ for Obese, Zn2+ for Obesity, morbid, Zn2+ for Obesityness, Zn2+ for Obseity, Zn2+ for Overobeseness, Zn2+ for Overobesity, Zn2+ for Severe obesity, Zn2+ for Super obese, Zn2+ for Truncal obesity, Zn2+ for Weight problem, Element 30 for Obesity, Mossy zinc for Obesity, SHG zinc for Obesity, Special high grade zinc for Obesity, Super high grade zinc for Obesity, Zinc (element) for Obesity, Zinc alloy for Obesity, Zinc alloys for Obesity, Zinc ions for Obesity, Zinc metabolism for Obesity, Zinc metallurgy for Obesity, Zinc pills for Obesity, Zinc poisoning for Obesity, Zinc Processing for Obesity, Zinc tablets for Obesity, Zinc tiles for Obesity, Zn2+ for Obesity, Zinc for Adipositas, Zinc for Adult Obesity, Zinc for Boddy wieght problem, Zinc for Clinical obesity, Zinc for Clinically obese, Zinc for Clinically severe obesity, Zinc for Corpulence, Zinc for Corpulent, Zinc for Dunlap disease, Zinc for Effects of obesity on health, Zinc for Environmental causes of obesity, Zinc for Exogenous obesity, Zinc for Fat dude, Zinc for Fat Guy, Zinc for Fat people, Zinc for Fat person, Zinc for Flabbiness, Zinc for Genetics and obesity, Zinc for Morbid obesity, Zinc for Morbidly obese, Zinc for Morbidogenic, Zinc for Obeast, Zinc for Obecity, Zinc for Obese, Zinc for Obesity, morbid, Zinc for Obesityness, Zinc for Obseity, Zinc for Overobeseness, Zinc for Overobesity, Zinc for Severe obesity, Zinc for Super obese, Zinc for Truncal obesity and Zinc for Weight problem.

 

Rate this treatment
for Obesity

Top treatments
for Obesity