Hormones are chemical messengers. Glands release them into the bloodstream, and they travel to distant tissues carrying instructions about growth, energy use, reproduction, stress response, sleep and more.
The system is organised in chains of command. A small region at the base of the brain monitors the body and sends instructions to a master gland just below it, which in turn signals other glands. When the level of a hormone rises high enough, it signals back up the chain to slow production. These feedback loops are what keep levels within a healthy range.
Three families of hormones
- Peptide and protein hormones. Chains of amino acids. This is the largest family and includes the hormone that controls blood sugar.
- Steroid hormones. Made from cholesterol. This family includes the stress hormone cortisol and the sex hormones.
- Amine hormones. Made from a single amino acid. Thyroid hormones and adrenaline are both made from tyrosine, and melatonin is made from tryptophan.
Two of the three families are built from amino acids, which shows how closely the hormone system depends on protein in the diet.
Where amino acids come in
- They are the direct building blocks of peptide and protein hormones.
- Individual amino acids are the starting point for thyroid hormones, adrenaline and melatonin.
- Hormones travel in the blood attached to carrier proteins and act through receptors on cells. Both are proteins, built from amino acids.
What influences hormone balance
- Sleep quality and a regular daily rhythm
- Long-term stress
- Overall nutrition, including enough protein and key minerals such as iodine
- Body composition and physical activity
- Age and life stage
This article is for general educational purposes only and is not medical advice.
Frequently asked questions
What is the endocrine system?
It is the network of glands that make hormones and release them into the blood to regulate the body's functions.
Are all hormones peptides?
No. Many are peptides or proteins, but others are made from cholesterol or from a single amino acid.
What is a feedback loop?
It is how the body self-regulates. When the level of a hormone is high enough, it signals the glands higher up the chain to reduce production.
How does diet relate to hormones?
Hormones, their carriers and their receptors are built from nutrients, especially amino acids. A balanced diet supplies the raw material.
Why does sleep affect hormones?
Many hormones are released in a daily rhythm tied to the sleep and wake cycle. Disrupted sleep disrupts that rhythm.
Is this medical advice?
No. This article is general educational information. Speak to a qualified healthcare professional about hormone-related concerns.