Scientists have discovered a connection between the amount of fat in the body at a certain age and the onset of puberty.
Imagine you’re in middle school. You’re going about your day, when suddenly you start noticing changes in yourself.
Your voice starts cracking more often and getting deeper. You’re growing taller at a rapid pace, and the pants you bought a few months ago are already too small. Your muscles feel different, and you’re more aware of everyone around you. It feels strange to look at your classmates. Your heart races when a certain someone walks by you in the hallway.
All these physical changes make you self-conscious. But you find comfort in knowing that you’re not alone. Many others in school, including some of your friends, are going through the same thing!
Puberty can be a confusing time for many of us. (Photo Credit : Nicoleta Ionescu/Shutterstock)
Puberty is a process that marks the beginning of physical maturity. But the changes in your body don’t just happen randomly, so how does your body know when it’s time to start this transformation into adulthood? What triggers such a significant revolution in our bodies?
Introducing The Team Of Players
All the changes you experience during puberty are caused by hormones – small molecules produced by specific organs in our bodies. These molecules travel through the bloodstream and target specific processes or areas for desired effects. For example, adrenaline, a hormone produced by the adrenal glands, helps us respond to emergencies by activating our “fight-or-flight” response.
The main hormones involved in puberty are estrogen and testosterone, known as sex hormones. They’re responsible for voice cracking, body shape changes, and the growth of additional hair.
Your sex organs – ovaries in females and testes in males – produce and release the sex hormones. However, they don’t do it voluntarily; the brain sends them the signal to produce hormones.
The brain sends this signal in the form of two hormones – luteinizing hormone (LH) and follicular stimulating hormone (FSH). Both of these hormones are produced by the pituitary gland, a small pitcher-shaped gland in the brain.
The pituitary gland has its own commander, the hypothalamus (a small region above the pituitary gland), which produces gonadotrophin-releasing hormone (GnRH). This hormone travels to the pituitary gland and tells it, “Hey, it’s time to release LH and FSH!”
The HPG Axis. This axis primarily controls the hormonal execution of puberty in our bodies. The arrow marks represent promotion or positive flow, while the blunt lines represent inhibition.
To ensure that everything happens in the correct sequence, the hypothalamus starts the puberty process by releasing GnRH. This is followed by the pituitary gland releasing LH and FSH, which eventually lead to the release of estrogen and testosterone.
The Hypothalamus-Pituitary-Gonadal (HPG) axis is the order of hormones and their source glands that regulate the development of our body in a time-dependent manner.
Children have minimal levels of sex hormones. It is only after the age of 8 that the body starts producing more sex hormones, leading to puberty. The hypothalamus has a checklist to determine when to initiate puberty. Once certain cues on the checklist are met, signaling molecules inform the hypothalamus, signaling that the checklist is complete. When all essential factors are checked off, puberty begins.
One important factor in the onset of puberty is the presence of fat molecules in the body. Puberty causes organ enlargement and tissue development, requiring a “critical amount” of fat molecules. This is why puberty is typically attained after the age of eight, as it takes several years for the body to accumulate enough fat molecules and nutrients to support growth.
If a person’s fat molecule percentage exceeds the “critical amount” before the age of eight, they may experience earlier puberty. Lifestyle also plays a role in puberty. Factors such as physical activity, hydration, diet, and stress levels can influence the hypothalamus’s perception of the body’s readiness for puberty. Higher stress and lower physical activity can increase sugar and fat molecules in the body, leading the hypothalamus to believe that the body can support reproductive development, thus initiating puberty.