What is a potential risk associated with very low body fat percentages?

Very low body fat percentages can lead to hormonal imbalances and decreased immune function due to the body not having enough fat to support various physiological processes. Body fat is essential for the production of hormones, including those related to reproductive health like estrogen and testosterone. When body fat levels drop too low, the body may struggle to maintain normal hormonal balance, which can disrupt menstrual cycles in females and affect libido in both genders.

Additionally, low body fat can compromise the immune system, as adequate fat composition is necessary for the proper functioning of immune responses. Without sufficient energy reserves, the body may not be able to respond effectively to infections or recover from illness, leading to increased vulnerability.

In contrast, other options suggest outcomes like enhanced metabolic rate, increased energy levels, and improved cardiovascular health, which are generally associated with healthy body composition, but do not hold true for individuals with extremely low body fat. The risks associated with very low body fat highlight the importance of maintaining a balanced and healthy body fat percentage for overall well-being and health.