Feedback loops
/explore/discover/feedback-loops/
This article explains what feedback loops are and how they work. It explains the difference between positive and negative feedback loops, and gives examples of how both are used in the body.

Corticotrophin-releasing hormone
/hormones/corticotrophin-releasing-hormone/
Corticotrophin-releasing hormone is the main element that drives the body's response to stress. It is also present in diseases that cause inflammation. Too much or too little corticotrophin-releasing hormone can have a range of negative effects.

Tertiary hyperparathyroidism
/endocrine-conditions/tertiary-hyperparathyroidism/
Tertiary hyperparathyroidism means excess production of parathyroid hormone that has escaped all normal body feedback controls and so persists even in cases where the initial cause (low blood calcium) has been corrected.

What is homeostasis?
/explore/discover/what-is-homeostasis/
Hormones are responsible for key homeostatic processes including control of blood glucose levels and control of blood pressure.

Follicle stimulating hormone
/hormones/follicle-stimulating-hormone/
Follicle stimulating hormone is produced by the pituitary gland. It regulates the functions of both the ovaries and testes. Lack or low levels of it can cause subfertility in both men and women.

Menstrual cycle
/explore/discover/menstrual-cycle/
The menstrual cycle is an important process that prepares the body for the possibility of pregnancy. Each stage is driven by reproductive hormones that are regulated by the pituitary gland.

Male contraceptives
/explore/discover/male-contraceptives/
There is a great deal of ongoing research into developing new male contraceptive options. However, currently, the only available male contraceptive options are undergoing a surgical procedure called a vasectomy and using a condom.

Thyroxine
/hormones/thyroxine/
Thyroxine is the main hormone secreted into the bloodstream by the thyroid gland. It plays vital roles in metabolism, heart and muscle function, brain development, and maintenance of bones.

Cortisol: KS4 article
/explore/discover/cortisol-ks4-article/
Cortisol (also known as hydrocortisone) is a steroid hormone that regulates a very wide range of processes throughout the body. It is perhaps most famous for its role in helping the body respond to stress.

Human chorionic gonadotrophin
/hormones/human-chorionic-gonadotrophin/
Human chorionic gonadotrophin is a reproductive hormone that is essential for establishing and maintaining early pregnancy.

Luteinising hormone
/hormones/luteinising-hormone/
Luteinising hormone is produced by the pituitary gland and is one of the main hormones that control the reproductive system.

Nelson's syndrome
/endocrine-conditions/nelsons-syndrome/
Nelson's syndrome is the name given to the enlargement of a pituitary gland tumour associated with excess secretion of adrenocorticotropic hormone following the surgical removal of both adrenal glands, usually to treat Cushing's disease.

Parathyroid hormone
/hormones/parathyroid-hormone/
Parathyroid hormone is secreted by the parathyroid glands and is the most important regulator of blood calcium levels.

Adrenocorticotropic hormone
/hormones/adrenocorticotropic-hormone/
Adrenocorticotropic hormone (ACTH) is produced by the pituitary gland. Its key function is to stimulate the production and release of cortisol from the cortex (outer part) of the adrenal gland.

Cortisol
/hormones/cortisol/
Cortisol is a steroid hormone that regulates a wide range of processes throughout the body, including metabolism and the immune response. It also has a very important role in helping the body respond to stress.

Dehydroepiandrosterone
/hormones/dehydroepiandrosterone/
Dehydroepiandrosterone is an important precursor hormone, and is the most abundant circulating steroid present in the human body. It has little biological effect on its own but has powerful effects when converted into other hormones such as sex steroids.

Dihydrotestosterone
/hormones/dihydrotestosterone/
Dihydrotestosterone, a hormone with powerful androgenic actions, causes the body to mature during puberty and is responsible for many of the physical characteristics associated with adult males.

Prolactin
/hormones/prolactin/
Prolactin is a hormone produced in the pituitary gland, named because of its role in lactation. It also has other wide-ranging functions in the body, from acting on the reproductive system to influencing behaviour and regulating the immune system.

Hypothalamus
/glands/hypothalamus/
The hypothalamus is a part of the brain that has a vital role in controlling many bodily functions including the release of hormones from the pituitary gland.

Testosterone
/hormones/testosterone/
Testosterone is a hormone that is responsible for many of the physical characteristics specific to adult males. It plays a key role in reproduction and the maintenance of bone and muscle strength.

What is HRT?
/explore/discover/what-is-hrt/
Hormone replacement therapy (or HRT) (also known as menopausal hormone therapy; MHT) is the replacement of female sex hormones oestrogen and progesterone in women to control symptoms of the menopause.

Growth hormone-releasing hormone
/hormones/growth-hormone-releasing-hormone/
Growth hormone-releasing hormone stimulates the secretion of growth hormone, an important regulator of growth, metabolism and body structure.

Oestriol
/hormones/oestriol/
Oestriol is a hormone made during pregnancy that can be used to measure foetal health and predict when birth may happen.

Are my hormones making me horny?
/explore/resources/podcasts/are-my-hormones-making-me-horny/
What’s the difference between sexual desire and arousal? How does the contraceptive pill affect your sex drive? Which hormone has recently been found to boost sexual arousal in both men and women?

Thyroid stimulating hormone
/hormones/thyroid-stimulating-hormone/
Thyroid Stimulating Hormone (TSH) is produced by the pituitary gland. Its role is to regulate (by stimulating) the production of thyroid hormones by the thyroid gland.

Adrenal glands
/glands/adrenal-glands/
The adrenal glands are small glands attached to the top of each kidney. The human body has two adrenal glands that release chemical messengers called hormones into the bloodstream. These hormones travel via the blood to have an action in other parts of the human body.

Thyroid gland
/glands/thyroid-gland/
The thyroid gland is part of the endocrine system and produces thyroid hormones, which are important for metabolic health.

Hormones in human reproduction
/explore/discover/hormones-in-human-reproduction/
Hormones are key players in human reproduction. They ensure everything happens at the right time, from puberty to menstruation and child birth. 

Female contraceptives
/explore/resources/female-contraceptives/
Contraceptives are medications and devices that are designed to prevent unintended pregnancies.

Is modern life overloading our stress levels?
/explore/resources/podcasts/is-modern-life-overloading-our-stress-levels/
We all know what it's like to feel stressed, perhaps this year more than most, but what are our stress hormones really doing to our minds and bodies?

Menopause
/endocrine-conditions/menopause/
The menopause is the time when menstruation stops because the ovaries stop producing hormones and releasing eggs each month. This usually marks the end of a woman's reproductive years.

Oxytocin
/hormones/oxytocin/
Oxytocin is a hormone that acts on organs in the body (including the breast and uterus) and as a chemical messenger in the brain controlling key aspects of the female reproductive system including childbirth and lactation.

Triiodothyronine
/hormones/triiodothyronine/
Triiodothyronine is a thyroid hormone that plays vital roles in the body's metabolic rate, heart and digestive functions, muscle control, brain development and function, and the maintenance of bones.

Can my pet pick up my stress?
/explore/resources/podcasts/can-my-pet-pick-up-my-stress/
S3:2 Do animals recognise when we are feeling the pressure? How can dogs help us when our stress hormones fail? And how has studying stress in horses helped us understand human hormones?

Oestrone
/hormones/oestrone/
Oestrone is a hormone produced by the ovaries, adrenal glands and fat. It is one of the major oestrogens in postmenopausal women.

Hormones and conservation
/explore/discover/hormones-and-conservation/
The study of animal reproductive systems and regular monitoring of reproductive and stress hormones is important for conservation.

Somatostatin
/hormones/somatostatin/
Somatostatin is a hormone that inhibits the secretion of several other hormones, including growth hormone, thyroid stimulating hormone, cholecystokinin and insulin.

Secondary hyperparathyroidism
/endocrine-conditions/secondary-hyperparathyroidism/
Secondary hyperparathyroidism is the release of increased amounts of parathyroid hormone (hyperparathyroidism), which is an appropriate response to low calcium or vitamin D levels in order to try to bring calcium levels back up to normal.

Melanocyte-stimulating hormone
/hormones/melanocyte-stimulating-hormone/
Melanocyte-stimulating hormone describes a group of hormones produced by the pituitary gland, hypothalamus and skin cells. It is important for protecting the skin from UV rays, development of pigmentation and control of appetite.

Primary hyperaldosteronism
/endocrine-conditions/primary-hyperaldosteronism/
Primary hyperaldosteronism is a condition where one or both adrenal glands make too much of a hormone called aldosterone. This hormone controls how much salt (sodium) and water the body absorbs (retains) from the kidneys. Retaining too much salt and water can cause high blood pressure.

Insulin
/hormones/insulin/
Insulin is an essential hormone produced by the pancreas. Its main role is to control glucose levels in our bodies.

Resistance to thyroid hormone
/endocrine-conditions/resistance-to-thyroid-hormone/
Resistance to thyroid hormone is a rare genetic condition where some body tissues do not respond normally to thyroid hormones produced by the thyroid gland. It may be associated with no symptoms or with features of both an overactive and underactive thyroid.

Melatonin
/hormones/melatonin/
Melatonin is mainly produced by the pineal gland and although it appears not to be essential for human physiology, it is known to have a range of different effects when taken as a medication.

Hirsutism
/endocrine-conditions/hirsutism/
Hirsutism is the presence of excess male-pattern hair growth in women and is commonly caused by an imbalance of hormones.

Hormones in pregnancy and labour
/explore/discover/hormones-in-pregnancy-and-labour/
Hormones play an important role in pregnancy and labour. They help make sure everything happens at the right time and in the right order.

Pre-eclampsia
/endocrine-conditions/pre-eclampsia/
Pre-eclampsia is a condition that arises during pregnancy in which the expectant mother experiences very high blood pressure and protein in her urine; it can lead to a range of complications.

Lipodystrophy
/endocrine-conditions/lipodystrophy/
Lipodystrophy is a condition in which the amount and/or distribution of adipose tissue (fat tissue) in the body is abnormal. Different types of lipodystrophy cause loss or re-distribution of fat tissue in different patterns.

Physiotherapist
/students/careers/physiotherapist/
Katherine Cook, Physiotherapist & Physiotherapy Lecturer: Physiotherapists help people of all ages to improve their health and wellbeing, there aren’t many areas of healthcare where you don’t find a physio working as part of the team.

Clinical Academic
/students/careers/clinical-academic/
Chioma Izzyengbaeyam, Director of the Pharmacology Intercalated BSc and Consultant Endocrinologist: I oversee the science degree that medical students undertake in the fourth year of their course in Imperial College School of Medicine.

Are everyday chemicals harming my health?
/explore/resources/podcasts/are-everyday-chemicals-harming-my-health/
There are chemicals all around us, but can they interfere with our hormones? Endocrine disruptors have been linked with a number of health problems, so for the final episode in the series we look at where these chemicals are found and whether we should be worried.

Obesity
/endocrine-conditions/obesity/
Obesity is when the body stores more calories as fat than it needs. It is becoming a growing public health and medical problem, linked to a lower quality and a shorter length of life.

Cushing's syndrome
/endocrine-conditions/cushings-syndrome/
Cushing's syndrome is the name given to the collection of signs and symptoms that occur when the body is exposed to too much of the hormone cortisol.

Does when I eat affect my weight?
/explore/resources/podcasts/does-when-i-eat-affect-my-weight/
Does when you eat affect your body weight? Do meal-timing based diets like intermittent fasting really work? How are your hormones involved and does this new diet fad stand up to scientific scrutiny?

Can I hack my hormones to beat ageing?
/explore/resources/podcasts/can-i-hack-my-hormones-to-beat-ageing/
Are there really chemicals inside us that could lead to some age-defying interventions in the future? Could our hormones hold the map to the fountain of youth?

Can I hack my hormones to beat jet lag?
/explore/resources/podcasts/can-i-hack-my-hormones-to-beat-jet-lag/
We explore the hormones behind our sleep-wake cycle, how they can get out of sync and why some athletes are totally immune to jet lag.

Is my soya latte messing with my hormones?
/explore/resources/podcasts/is-my-soya-latte-messing-with-my-hormones/
Should I be concerned about growth hormones in a cow's milk cappuccino? Are the plant oestrogens in a soya latte affecting my risk of cancer? Will almond milk damage my thyroid? 

Is my diabetes my fault?
/explore/resources/podcasts/is-my-diabetes-my-fault/
Is type 2 diabetes really a “lifestyle disease”? Why do some people develop diabetes even though they’re eating healthily while many obese people escape the disease? How can your environment shape your diabetes risk before you’re even born?