Which of the following is true about leptin?

• A. Obese individuals often display insensitivity to leptin.
• B. Leptin is released by the thyroid.
• C. Leptin directly influences your metabolism by increasing your BMR.
• D. Leptin is the primary hormone for hunger signaling.

Answer: (A)

Verified step by step guidance

1. Leptin is a hormone primarily produced by adipose (fat) tissue, not the thyroid. Begin by understanding that its primary role is to regulate energy balance by inhibiting hunger, which is different from directly signaling hunger.
2. Leptin works by signaling the hypothalamus in the brain to reduce appetite and increase energy expenditure. This is how it indirectly influences metabolism, but it does not directly increase the Basal Metabolic Rate (BMR).
3. In obese individuals, leptin levels are often elevated due to the higher amount of fat tissue. However, these individuals may develop leptin resistance, meaning their bodies do not respond effectively to the hormone's signals, leading to continued overeating and reduced energy expenditure.
4. Leptin is not the primary hormone for hunger signaling. That role is primarily attributed to ghrelin, which is produced in the stomach and signals hunger to the brain.
5. To determine the correct answer, evaluate each statement based on the scientific understanding of leptin's role in the body. The correct statement is that 'Obese individuals often display insensitivity to leptin.'