The Power of Hormones: The new science of how hormones shape every aspect of our lives

by Max Nieuwdorp

Waarom laat acute stress ons zo heftig reageren op een spannende situatie? En hoe komt het dat afwijkende hormoonspiegels verantwoordelijk waren voor een aantal cruciale beslissingen in onze wereldgeschiedenis?
Onze hormonen spelen bij veel alledaagse zaken een grote rol – vanaf het moment dat we verwekt worden tot de seconde dat we onze laatste adem uitblazen. Zo regelen ze onze ontwikkeling in de puberteit, zorgen ze voor een succesvolle zwangerschap en zijn ze leidend bij het verouderingsproces. De wetenschappelijke kennis over de manier waarop hormonen hun functie in ons lichaam uitoefenen, is in de afgelopen zeventig jaar enorm toegenomen. Tegelijkertijd zijn vele inzichten onderbelicht gebleven, zoals de grote invloed van onze darmbacteriën op onze hormoonhuishouding en de ontwikkelingen die het vrouwelijk lichaam doormaakt tijdens de overgang.
In dit fascinerende boek, waartoe Max Nieuwdorp werd geïnspireerd door het dagelijkse contact met zijn patiënten, wordt de macht van onze hormonen op alle vlakken en in alle levensfasen voor het eerst kristalhelder en tot in detail beschreven.

Genres: Nonfiction, Health, Science, Audiobook, Biology, Ebooks, Psychology

352 pages, Hardcover

Published May 23, 2024

Reviews

[Robin Mandell · Rating 2 out of 5]

So, I think this is a good book, and an important book.
It’s engagingly written, even in translation.
The average person doesn’t know a lot about the endocrine system overall so I’m really glad there is a book on this topic geared towards the general population.
Why did I only give this two stars then?
Inaccuracy and oversimplification.
1. This author still subscribes to the inaccurate belief that a “healthy weight” can be calculated based on a person’s height and current weight. The scientific support for this is weak at best. Relatedly, he asserts that being overweight *causes* particular diseases and poor health. While he calls out fat shaming as harmful, this author ends up repeating a lot of inaccuracies as scientific facts, and naming both correlations and contributing factors as causes.
All of this is really too bad because he does have some useful things to say about the ways that hormones affect metabolism, satiety, and stress.
2. This doctor includes cancer in a list of diseases that he labels “diseases of affluence.”
Last time I checked, cancer is caused by a variety of factors, everything from genetics to prolonged exposure to environmental toxins . There is no clear clarification on which types of cancer he is referring to so this statement is misleading, directing the reader to believe that cancer is caused by a modern and western diet and lack of exercise.
3. We get a clear and detailed description of pregnancy and fetal development. However, in the chapter where all of this is spelled out, the author fails to tell us that intersects conditions are common. In fact, the existence of intersects people is given just a brief mention in the chapter on gender and sexual orientation Which means that in the chapter on pregnancy and early development the idea that there are only two biological sexes with almost no variation is reinforced. The last time I looked, the estimate was about one in 2000 babies will be born with some type of intersex characteristics. Those are not rare variations.

[Gwynn_Sky · Rating 5 out of 5]

In general, we know very little about the human body and physically there is a big difference between the female and male bodies. Doctor Nieuwdorp has written a comprehensive book that gives an understandable picture of the currently known facts for the reader. The human body and its hormone balance is an incredible system that we have begun to observe in the last few decades, and it tries to summarize these and illustrate them with examples for the reader. A readable, useful book.

[Robbe Rooms · Rating 3 out of 5]

Interesting topic and clear and accessible language, but the transphobic language was disappointing in a book from a doctor who works with trans people. Using a deadname instead of someone’s real name is not done. This made the chapter I was the most exciting about the one that dragged down the rest of the book.

[Aliyah Spacey-Smith · Rating 1 out of 5]

Kinda annoyed with this book tbh. I thought it was going to go into detail around the different hormones and how powerful they can be (following the title) and maybe an indication around how lifestyle can indicate hormones!!? but instead, had an explanation of hormones throughout life, which maybe would’ve been helpful/interesting if written in a different way but the constant bouncing between studies, giving a full history on the discovery of hormones, but not actually explaining anything in particular detail, just really wasn’t for me.

[Magdalena Kruszyńska · Rating 5 out of 5]

4.5🎧
Recommended for everyone who want to be educated about their own body. Lots of very interesting information presented in language accessible for everyone. I’ve learned soo many things about hormones and find out that many symptoms have scientific explanations.
One quote I really liked-
‘’Everyone wants to become old, but nobody likes being old.’’

[Maaike G · Rating 4 out of 5]

3.5/5

[Charlotte · Rating 4 out of 5]

I appreciate Nieuwdorp’s descriptions of how various hormones, medications, and other factors impact men vs. women. He calls out how clinical trials, since the birth of modern medicine, have focused on men (because their hormones are more constant from week to week), and then medical professionals would assume that women’s physiology was just a “light” version of men’s. This has led to enormous information asymmetry between men and women’s health, and women’s health conditions continue to be misdiagnosed and poorly addressed as a result.

ie, Women’s! Health! Is! Grossly! Under! Researched!

[Ellen · Rating 3 out of 5]

Tad repetitive but very interesting - hormones are so cool!!!

[Kirsten Gorter · Rating 2 out of 5]

Zeker een leerzaam boek, met ook de nodige nieuwe interessante feitjes voor mij. Maar, de schrijfstijl was niet prettig. Veel tekst, vaak van de hak op de tak. En na sommige hele inhoudelijke en serieuze stukken kwam dan opeens een heel flauw ‘grapje’ of bijvoorbeeld een vergelijking met bekende acteurs. Zo niet gepast.

[Leonie · Rating 4 out of 5]

Ik heb dit boek in een middag in de bibliotheek gelezen en ik schat een kwart van de tekst gelezen. Het is een goed boek om alleen de delen die je interesseert van te lezen (in mijn geval slaap, gewicht, seksualiteit, auto immuunziektes). Zou zeker niet het hele boek lezen, daarvoor is het wat te droog en zit er geen opbouw of verhaal in. Als je een interesse hebt in gezondheid heeft het ook veel overlap met dingen die je al weet. Maar ik zou het dus aanraden om eens door te gaan, de schrijver legt de werking van hormonen op een hele toegankelijke manier uit.

[Anna Sawlani · Rating 4 out of 5]

I am not scientifically minded, and I really enjoyed how accessible this book was for me. I listened to it quite slowly, treating it almost like mini podcasts for me to dip in and out of, but it made it really easy to be able to treat it this way. Such an engaging book, and SO interesting. Some of the things I’ve learnt are super fascinating. I found some chapters less personally interesting than others, but regardless it was aways engaging and has a good narrative.

[Anne-Marie Laberge · Rating 3 out of 5]

I did find this book interesting
RATING : 3.5 (1) I will quote but probably not re-read, 2) hope to find another book on the subject to recommend before this one, but I'm still searching)

Wanting to understand the scientific facts behind mood changes observed and probably caused by hormones, this title caught my eyes.
Even with lots of research cited throughout this book, the conclusion remains: a lot is still unknown and more needs to be scientifically demonstrated.
Some of his deduction are, for me, not solid enough or logical. Sometimes I felt like the pregnant mothers were to blame for all the worlds problems... This said, the author was able to explain in common words a lot of hormonal phases and many parts were interesting !

As a biblical counselor, I will add that even if Nieuwdrop quotes the Bible, he does so as exemples and not because he believes in YHWH or salvation in Christ.

[Svetlana · Rating 5 out of 5]

To quote Max Nieuwdorp: “It was an informative process, especially because I kept arriving at the sobering conclusion that we actually know so little about the cause of our diseases.” Or how to measure all the fascinating interactions of hormones. Or how to fix things that go wrong with them, with a degree of certainty. Fascinating read.

[Ilse · Rating 2 out of 5]

Sorry ik vond het echt teveel info. Goed wel goeie info dus 2,5 ☆ maar voor mij persoonlijk kwam ik er niet door johhhh.

[Liselore · Rating 5 out of 5]

Super interessant boek!

Hoewel het boek gebaseerd op wetenschap geschreven is, leest ie toch goed door. Veel geleerd!

[Annerieke Ten Haken · Rating 5 out of 5]

Fascinerend boek over het lichaam en al de hormonen. Erg complex maar fijn geschreven met leuke weetjes en voorbeelden.

[Chris Mokken · Rating 3 out of 5]

Aardig om te lezen omdat ik de man ken, maar het boek is vrij breed opgezet; niet alle onderwerpen spraken mij aan.

[Robin Yasmin · Rating 4 out of 5]

Leuke informatie, maar wel erg van de hak op de tak.

[Paloeka · Rating 2 out of 5]

Ik was super enthousiast om dit boek te lezen, aangezien ik graag meer wil(de) leren over hormonen. Het boek is op zich wel makkelijk leesbaar, maar soms ook een beetje chaotisch. Dit laatste is niet heel erg, zeker niet met de uitgebreide index in de achterkant van het boek (ik had de papieren versie gekocht).
Maar teleurstelling kwam snel. Het is duidelijk dat Max Nieuwdorp veel kennis over hormonen heeft, dat stuk is vaak goed geschreven, maar zodra het "vertaald" wordt naar socio-culturele of historische gebeurtenissen is het zeer problematisch. Zijn taalgebruik kan daarin zelfs best kwetsend zijn. Ik heb het idee dat hij dead-named (oude namen gebruikt van mensen die in gendertransitie zijn geweest). Daarnaast fatshamed hij en is soms seksitisch. Ik besprak dit boek met een vriendin van mij en zij was ook verbaasd dat dit boek dit jaar was uitgekomen en niet 50 jaar geleden. Ik raad de auteur aan om terug de schoolbanken in te gaan en vakken binnen sociale en historische wetenschappen te volgen.

Het boek inspireert mij wel om in endocrinologie te duiken, om dit boek te kunnen herschrijven. Hormonen zijn fantastische molecule die sommige/veel dingen in ons lichaam kunnen bepalen. Wat ik juist zo fantastisch vind is dat ze zo fluide zijn, dat levels verschillen en zo juist de diversiteit van het lichaam laten zien (en niet de blame en shame wat in dit boek naar voren komt).

[An · Rating 2 out of 5]

There are so many arbitrary simplifications and noticeable hiccups throughout the book. I wouldn’t recommend it, to be honest. Below are some random thoughts and quotes to emphasize my point:


i am on chapter 2 where the author talks about endocrine disruptors and phytoestrogens and the author mentions this

Think, for example, of vegetarian meat substitutes, but also of the waste from processed soya beans (soya-bean meal), which is one of the most important sources of protein for pigs and poultry. While it remains unclear whether these natural endocrine disruptors can be harmful to our offspring,24,25 we must be vigilant. Studies have shown that soya products (in infant formula) can affect the development of the child’s brain.26

i read the paper cited in the last line "26" {Exposure to soy-based formula in infancy and endocrinological and reproductive outcomes in young adulthood by B L Strom} and the paper clearly says in the conclusion

Exposure to soy formula does not appear to lead to different general health or reproductive outcomes than exposure to cow milk formula. Although the few positive findings should be explored in future studies, our findings are reassuring about the safety of infant soy formula.

idk why the author doesnt clearly say the conclusion of proper risk assesment analysis. not to mention all of the studies cited were from 2000-2001s , ik funding is always low so citing a recent one is kinda hard but oof the sampel size is about 800 people

Omaga this book is making me rage! I don’t understand why, in 2024, it’s still perpetuating the same binary belief that in prehistoric times women were always nurturing and men were hunting. It’s so much more complicated than that! There are elements of communal parenting, and some recent, well-publicized archaeological studies from after 2020 show that women were also big game hunters.
the roles often varied greatly depending on factors like the tribe's location, the season, and the gender ratio. “Eve” by Cat Bohannon isn’t a perfect book, but at least it explores these issues with multiple theories.
Not to mention, why isn’t he addressing the sociological factors behind gender differences in things like hobby preferences and toy choices among infants and teens? Cordelia Fine’s book on neurosexism has talked about this shit

atleast the chapter(4) on gender identity and sexual preference wasnt that bad although ig it was very basic so there is nothing much to mess up with
also ik sex hormones are more studied and general people have more interest on it but really? non sex hormones had only about 3 chapters and sex hormones have approx 7 chapters :cringeHarold:
i still feel stupid about peptide, adrenal, thyroid , pancreatic hormones even after readint this book

[Wayne Augusto · Rating 3 out of 5]

What I loved about this book is that is written by a doctor citing scientific researches but made for people not in the medical field!! and it is so eye opening!!! So much if not everything in our life is related to hormones! But we don’t seems to think about it…. Or ever make a correlation. Hence this a book that everybody should read. Really interesting facts put in an easy-to-read narrative making it relatable and not boring. I would describe this book as light and informative. A must read.

[Greet Bakker · Rating 5 out of 5]

In dit boek wordt op boeiende wijze uitgelegd hoe onze hormonen werken en welke invloed ze hebben op ons leven. Leuke voorbeelden uit de dagelijkse praktijk van de schrijver en ook diverse verwijzingen naar de geschiedenis en de bijbel. Een absolute must-read!

[Justin Drew · Rating 5 out of 5]

The Power of Hormones: The New Science of How Hormones Shape Every Aspect of Our Lives by Max Nieuwdorp is a fascinating look at the world of our hormones and the endocrine system. It looks at the idea that our hormones allow us to be. It’s strange to find that there are so few books that cover this subject..
- Hormones are chemical messengers made by glands in the endocrine system. They travel through the bloodstream to organs and tissues, telling them what to do and when to do it.
- Examples: Insulin lowers blood sugar, adrenaline increases heart rate and energy, cortisol manages stress, thyroid hormones control metabolism, oestrogen & testosterone regulate reproduction and development. Hormones help control almost every major body process.
- Modern culture tends to treat hormones as technical footnotes to health: something measured in blood tests, corrected with medication, or blamed when things go wrong. Endocrinologist Max Nieuwdorp dismantles this narrow view. Hormones, he argues, are not peripheral chemical messengers but the organising force of human life - shaping who we are, how we develop, how we relate to others, and even how future generations will live.
HORMONES – THE INVISIBLE GOVERNOR AND CONDUCTOR
- This is not a book about optimisation or biohacking-It’s about humility. Nieuwdorp shows that identity, behaviour, fertility, appetite, mood, aging, and disease all emerge from a delicate hormonal choreography that evolved for a world very different from our own. We do not simply “have” hormones. We are their expression.
- The endocrine system coordinates major life changes such as growth, puberty, and reproduction.
It also regulates essential processes like sleep, heart rhythm, metabolism, and digestion, influencing every cell. The system works through glands, hormones, and cell receptors: Glands (3 in the brain, 7 elsewhere in the body) produce hormones. Hormones travel via the bloodstream to target cells. Receptors on or inside cells bind hormones, triggering changes in cell activity. Examples include the thyroid gland that produces hormones that control energy use, affecting breathing, heartbeat, temperature, and digestion.
- Hormones also influence pregnancy, birth, breastfeeding, and can affect mood by altering brain chemicals like serotonin.
- Behaviour is shaped by hormones, brain activity, and social factors—not hormones.
- Disruptions from stress, illness, or diet can cause disorders such as diabetes where the pancreas produces too little insulin or in thyroid disorders: Too little or too much thyroid hormone causes fatigue, depression, weight loss, or irritability.
- Most of the time, the endocrine system maintains balance, enabling growth and adaptation.
BIOLOGY AND HORMONES SHAPE IDENTITY
- One of the book’s most striking ideas is that the self is biologically dependent. Nieuwdorp draws on the late novelist Hilary Mantel’s reflections on living with an endocrine disorder, describing how hormonal disruption altered not just her health but her sense of who she was. When hormone systems falter, people often report feeling alien to themselves — emotionally flattened, impulsive, anxious, or detached.
- This observation destabilises a comforting fiction: that personality and identity sit safely above biology. Instead, Nieuwdorp demonstrates that hormones shape perception, motivation, memory, and emotional tone, binding physiology and psychology together. Changes in hormone levels don’t simply “influence mood”; they can reconfigure the way a person inhabits the world.
- The implication is unsettling but clarifying. The continuity of the self is not guaranteed by willpower or character alone, but by fragile biochemical systems working largely outside our awareness.
MODERN LIFE IS AN ENDOCRINE STRESS TEST
- A recurring theme is that our hormonal systems evolved for scarcity, simplicity, and intermittent stress — not abundance, pollution, and chronic stimulation. Nieuwdorp traces how endocrine disruptors, ultra-processed food, synthetic hormones, plastics, pesticides, and constant psychological stress interfere with feedback loops refined over millions of years.
- Historical case studies give this argument moral weight. From Rachel Carson’s Silent Spring to the catastrophic use of medication (DES) in pregnancy, the book shows how well-intentioned interventions repeatedly underestimated the interconnectedness of hormonal systems. Because hormones operate at vanishingly small concentrations, even minor interference can produce disproportionate harm. The lesson is sobering; biological power does not confer biological control.
THE BRAINS ROLE IN HORMONES
- The book excels at making complex endocrinology legible without diluting its power. Nieuwdorp repeatedly returns to the hypothalamus and pituitary gland — tiny structures buried deep in the brain — which act as the central command centre of the endocrine system. These glands sit within the limbic system, the same neural network responsible for emotion, memory, and motivation.
- This anatomical fact dissolves the artificial divide between “mental” and “physical” illness. Stress, depression, metabolic disease, infertility, and immune dysfunction often share hormonal roots. Emotion does not merely affect the body; it is biologically embodied through endocrine signalling. Health, in this framing, is not about isolated organs but about system-wide coordination.
DEVELOPMENT BEGINS BEFORE WE ARE BORN
- The effects of hormonal fluctuations during a pregnancy can have a lasting influence on the child’s developing brain and body.
- Hormonal influence begins long before birth. Nieuwdorp describes pregnancy as a period of extraordinary vulnerability and precision. In the first trimester, a foetus is entirely dependent on maternal hormones; only later does it begin producing its own. The thyroid — essential for brain development and metabolism — forms early, underscoring how foundational endocrine systems are to life itself.
- Disruption during these critical windows can have lifelong consequences. Even more striking, those effects can extend beyond the individual. Hormonal environments during pregnancy can alter gene expression in ways that affect children and grandchildren — a phenomenon documented most vividly in studies of the Dutch Hunger Winter, where prenatal famine exposure increased rates of obesity, diabetes, and cardiovascular disease across generations. It wasn’t just mothers effected – but their children and grand-children.
- “If you are exposed to the stress hormone cortisol early in life, certain genes are calibrated differently for the rest of your life.”
- “Severe chronic stress during pregnancy can cause irreversible damage to the neurological development of foetuses – just think, for example, of children born during wars or other violent conflicts. In such cases, the child’s critical development period coincides with the period in which the stress hormones in the mother’s blood are elevated.”
- “In a large-scale Danish population study of 1.3 million babies born between 1973 and 1995, researchers found a link between major stress and intense grief in the first trimester of the pregnancy (such as the death of a loved one or another trauma) and an increase in the number of deformities and premature births.”
- “Emotional stress in healthy pregnant women is also detrimental to the motor and cognitive development of their two-year-old children.”
- Hormones, Nieuwdorp suggests, act as a biological memory system, encoding environmental experience into future bodies. If you look at the life cycle of a salmon-it is born in freshwater rivers, swims into the ocean and adapts to seawater and after a few years returns to the place its born (this appears to have some role in smell-if you knock out its ability to smell, it struggles to find its way home). Upon its return, it changes form again to adapt to fresh water, mates and then disintegrates and the next cycle of new salmon emerges. Or monarch butterflies – born as caterpillars, turn into a butterfly, and every fifth generation returns to the trees if emerged from five generations previous and goes through the cycle again. DNA contains memories and hormones conduct the acts for these changes to occur.
FERTILITY IN A TOXIC WORLD
- Perhaps the most alarming section of the book concerns fertility. Nieuwdorp reviews evidence that sperm counts in Western men have halved since the 1970s, alongside declines in sperm motility and quality. Environmental toxins — many with oestrogen-like effects — are strongly implicated.
- Women face a different vulnerability. Because they are born with a finite number of eggs, damage incurred in utero or early childhood may remain invisible for decades, only emerging during attempts to conceive. Fertility, in this view, is not merely personal or genetic. It is environmental, cumulative, and intergenerational.
HORMONES AND REPRODUCTIVE HEALTH
- Undescended Testes: Important to review as it impacts hormonal development and fertility.
- Contraceptive Pill & Memory: Women on the pill tend to recall stories more factually (like men), while those not on the pill retain emotional details better. Hormones influence cognitive processing.
- Endocrine Disruptors: Chemicals like plastics can harm child development and have been observed in animals too.
CHILDHOOD AND ADOLESCENCE
- Growth Patterns: Example from the Netherlands: Historically tall population possibly due to dairy consumption, but recent trends show reduced height-potentially linked to sleep deprivation or other factors.
- Hormones shape growth, puberty, and cognitive development. However, environmental factors (diet, sleep, endocrine disruptors) influence height and maturation.
- In early pregnancy, all foetuses start with the same genital structures. Without a Y chromosome, these structures develop into female reproductive organs. When a Y chromosome is present, it triggers the production of substances, particularly anti-Müllerian hormone (AMH) and testosterone-that cause female structures to disappear and male genitalia to form. Sexual differences begin around week 7 and genitalia differences occur between week 8-12.
- AMH plays two major roles:
- Early development: In the first two months, AMH prevents the formation of female organs, allowing testosterone to shape male development.
- Brain development: AMH levels stay high in male foetuses, and research (e.g., in mice) suggests it may influence brain development related to behaviours like aggression and dominance. This raises the possibility that AMH could contribute to the higher rates of autism and ADHD seen in boys, though behaviour is influenced by many factors.
- After birth, mothers experience high oestrogen levels for about two years, which can affect emotions and behaviour. Pregnancy hormones also alter taste, often causing early aversions to bitter foods and later cravings for salty or sour flavours.
- Oxytocin plays a key role in bonding. It is released during labour, triggers milk let-down when a mother hears her baby cry and increases in adults when they have affectionate contact. Children deprived of social bonding often have low oxytocin and may show autism-like behaviours. Early research suggests oxytocin treatment can increase sociability in autistic individuals, but more evidence is needed because autism has many contributing factors.
LOVE AND ATTRACTION
- In Why We Love, Anna Machin explains that love is powered by an evolutionary neurochemical system—a blend of hormones that drives humans to form, strengthen, and maintain relationships essential for survival. She describes how oxytocin fosters trust and deep bonding, dopamine fuels the excitement and reward of early attraction, serotonin shifts contribute to early obsession, beta-endorphin supports long-term comfort and security, and vasopressin reinforces commitment and loyalty. Together, these hormones shape each stage of love - from the dopamine-driven thrill of early attraction to the serotonin-linked infatuation phase, and finally to the stable long-term bonds supported by oxytocin, vasopressin, and beta-endorphin-making love both emotionally powerful and biologically purposeful.
SEXUALITY AND GENDER
- The book argues that homosexuality is often considered abnormal by many who are against it, but animal homosexuality is common in the natural world. Over 65,000 species exhibit same-sex behaviour, showing it’s natural. Many still reproduce heterosexually.
- Sex vs. Gender: Sex is biological (between your legs); Gender is identity (between your ears).
- Hormones and Social Behaviour: Certain hormones promote bonding but can also trigger aggression toward outsiders.
APPETITE, HUNGER, AND THE ILLUSION OF CHOICE
- Nieuwdorp devotes considerable attention to hunger which he describes as the deepest and oldest human sensation. Appetite is governed not by a single “hunger hormone” but by a complex interplay of ghrelin, leptin, insulin, GLP-1, dopamine, and stress hormones interacting with ancient brain circuits.
- In environments of abundance, these systems malfunction predictably. Ultra-processed food exploits reward pathways designed for scarcity, while chronic stress amplifies appetite and fat storage. Weight gain, the book argues, is not primarily a failure of discipline but a biological response to mismatch.
“Hunger is probably the oldest feeling on earth. We have been plagued with it for billions of years and people have tried all sorts of ways to take control of it. Hunger is more deeply entrenched in our bodies than feelings of love, awe and happiness; deeper even than other serious concerns like thirst, fear and shortness of breath.”
- This framing neither absolves responsibility nor indulges fatalism. Instead, it redirects attention from moral judgment to structural causes.
THE GUT MICROBIOME SUPPORTS AND MAINTAINS HORMONAL BALANCE.
- The gut microbiome, an active, two-kilogram community of bacteria, fungi, and viruses, plays a crucial role in keeping our hormones balanced by aiding digestion, nutrient absorption, and producing hormone-related compounds. These microbes communicate with the brain and endocrine system, helping generate neurotransmitters like serotonin and dopamine and influencing stress and sex hormones, meaning imbalances can contribute to issues such as anxiety, depression, and autoimmune disorders. Our gut microbial makeup begins shaping early in life and is influenced by factors such as mode of birth (vaginal delivery versus C‑section), breastfeeding, diet, and antibiotic exposure. A diverse, well-balanced microbiome is vital for training the immune system and supporting metabolic health. A diverse microbiome is essential for immune training and metabolic health, and emerging approaches such as targeted probiotics and faecal transplants show promise for improving hormonal balance and treating related conditions.
PARENTING, BONDING, AND TRANSFORMATION
- One of the book’s quieter triumphs is its exploration of parenthood as a hormonal transformation. Pregnancy, birth, and caregiving reshape brains as well as bodies. Oxytocin facilitates bonding and emotional attunement; testosterone often drops in new fathers, increasing empathy and caregiving behaviour.
- Remarkably, behaviour feeds back into biology. The more time fathers spend caregiving, the more their hormone profiles adapt. Parenting, Nieuwdorp shows, is not simply learned — it is biologically induced.
AGING, EXCESS, AND BALANCE
- In its final sections, The Power of Hormones turns to aging and longevity. Excess of sugar, calories, stress, and stimulation accelerates hormonal wear and tear. Nieuwdorp links fructose metabolism to cellular aging and telomere shortening, reinforcing the idea that longevity emerges not from optimisation but restraint.
- The endocrine system rewards balance and punishes arrogance. Attempts to override it-through performance-enhancing drugs or hormone manipulation often backfire, producing infertility, cardiovascular disease, liver damage, issues with urinating and premature aging.
- Menopause: Only humans and two whale species experience it. Evolutionary role: Grandmothers aid offspring survival. Longer breastfeeding reduces menopausal symptoms. Oestrogen decline affects memory; supplementation can restore cognitive function.
- Sex Differences Over Time: Differences diminish with age. Men lose hair; women may gain facial hair.
- Aging Effects: Loss of smell, disrupted circadian rhythm and reduction in bone mass.
- Alzheimer’s: Twice as common in women; hormonal factors contribute.
- Depression in Men: Increased risk with age; suicide rates higher in men.
HOW HORMONES AND HOMEOSTASIS WORK
- Homeostasis means keeping the internal environment stable, even when things around you change.
The body constantly works to keep conditions just right, such as: Temperature (~37°C), Blood sugar levels, Water balance, pH levels, Blood pressure. It’s like the body's internal thermostat and balancing system.
- How Hormones Help Maintain Homeostasis: Hormones and homeostasis are deeply connected.
- Example: Blood Sugar Control: when blood sugar is too high the pancreas releases insulin, cells absorb sugar, Blood sugar drops back to normal. When blood sugar is too low: The pancreas releases glucagon, the liver releases stored sugar, levels rise back to normal. This is a negative feedback loop - the body corrects the change by producing the opposite response.
- Stress Response: When stressed - the adrenal glands release adrenaline and cortisol. These increase heart rate, breathing, energy and focus. Once the threat is over, hormone levels drop and the body returns to balance.
- Hormones keep homeostasis running. Homeostasis ensures that hormones are made and released at the right times. If hormone levels become too low or too high, homeostasis is disrupted. If homeostasis is disrupted (e.g. chronic stress, illness, poor diet), hormonal systems can malfunction.
- Understanding this connection explains why stress affects digestion and sleep, poor diet disrupts blood sugar and energy, dehydration affects hormones and mood, hormone disorders (thyroid, diabetes) affect the whole body. Everything is connected through this constant balancing act.
A BIOLOGY OF HUMILITY
- The Power of Hormones power lies in reframing human life as deeply biological yet profoundly relational-shaped by environment, culture, stress, care, and time.
- Nieuwdorp leaves the reader with an unsettling but necessary insight: we are far less autonomous than we imagine, and far more interconnected — across systems, societies, and generations-than we prefer to admit. Hormones do not merely regulate our bodies. They quietly govern our lives. I learnt a lot and loved it.

[Maja Fredebold · Rating 2 out of 5]

It’s a very interesting topic with an all over the place storyline. Could have been a brilliant book, ended up really frustrating me.

Gets really repetitive towards and end. He’ll explain some parts in painful detail but fails to explain the really important and interesting stuff in depth.

[Ankedesign · Rating 3 out of 5]

Leuk boek als je houdt van dingen als de populair wetenschappelijke boeken van Ap Dijksterhuis etc. Leest lekker weg, interessante info over wat hormonen doen met je lichaam.

[Saskia Jacobs-beukers · Rating 4 out of 5]

Een interessant en leerzaam boek van Prof. dr. Max Nieuwdorp (endocrinoloog en internist ) over onze hormonen. Hoe werkt het nou echt. Alles over de kracht van onze hormonen

Waarom reageren we zo heftig op een spannende situatie? Hoe komt het dat mannen en vrouwen als ze ouder worden meer op elkaar gaan lijken? En waarom hebben oudere mensen meer behoefte aan zout eten?

Onze hormonen spelen bij veel alledaagse zaken een grote rol – vanaf het moment dat we verwekt worden tot de seconde dat we onze laatste adem uitblazen. Zo regelen ze onze ontwikkeling in de puberteit, zorgen ze voor een succesvolle zwangerschap en zijn ze leidend bij het verouderingsproces. De wetenschappelijke kennis over de manier waarop hormonen hun functie in ons lichaam uitoefenen, is in de afgelopen zeventig jaar enorm toegenomen. Tegelijkertijd zijn veel inzichten onderbelicht gebleven, zoals de grote invloed van onze darmbacteriën op onze hormoonhuishouding, de ontwikkelingen die het vrouwelijk lichaam doormaakt tijdens de overgang en de afname van mannelijke hormonen tijdens de andropauze.

In dit fascinerende boek, waartoe Max Nieuwdorp werd geïnspireerd door het dagelijkse contact met zijn patiënten, wordt de macht van onze hormonen op alle vlakken en in alle levensfasen toegankelijk en uitgebreid beschreven.

[Sienna · Rating 2 out of 5]

2 stars
This book was not what I expected it to be.

I assumed from the title of the book that it would be broken down into here is this organ, this is the hormone, and this is the function of the body it helps activate or run. As someone who does not naturally produce her hormones I was interested in finding out what other bodily functions may be working harder due to my health condition and this book was never intended to be that.

I understand the book was going to discuss pregnancy and the breakdown of the female body as all these interesting hormonal changes occur, but I didn’t expect this to be such a large portion of the book.

The last point I want to make is for a book titled Power of Hormones, the author will make a statement of how hormones run something, but then state the environment and current conditions of the person. Trust me, I believe the environment you grew up in is a huge factor, but bringing it up so much after every chapter that every case is situational because outside factors weaken your points. If everything is situational, why did we need this book if every case is different?

[Rudi · Rating 5 out of 5]

Het boek is mooi verhalend geschreven over de impact van hormonen binnen onze levensfasen , voor deze lezer was er behoorlijk veel nieuwe informatie die op een leuke manier gebracht werd , die hormonen fabrieken lijken ons gedrag en humeur nogal veel te beïnvloeden, maar hoe deze fabrieken precies werken en hoe zij beïnvloed worden zijn nog veel vraagtekens, het onderzoekwerk is nog niet ten einde , veel vragen blijven over , zijn het mijn hormonen of de hormonen ?kunnen deze worden overgedragen en hoe ? , en in hoeverre kunnen/moeten we de speelbal zijn van die dingen ? , bacteriën, virussen, schimmels, en nu ook die hormonen, dan nog een hiërarchisch systeem erbij , in hoeverre hebben we dan zelf nog iets in de pap te brokken ? Dan speel je niet met de bal dan ben je de bal , en in de rechtbank een bal met nogal wat verantwoordelijkheid ,

[Alona Tytarenko · Rating 3 out of 5]

I was left with a weird feeling after finishing this book. The last part conclusion, which was about aging boiled down to "don't eat sugar," felt inaccurate, especially after reading more comprehensive books on aging. There wasn't even a mention of avoiding animal products or saturated fats, both of which are known to contribute to aging. If the author didn't research these areas, it feels misleading to provide such narrow advice.

Moreover, the book often strayed from the topic of hormones more than it should have. Beyond just explaining the structure of the endocrine system, I expected to learn more about how hormone concentrations present from birth influence our personality traits (e.g., the effects of high or low serotonin levels). Unfortunately, this aspect was not explored in depth, which left me wanting more.
I did learn something new for sure!

[Agata · Rating 4 out of 5]

I’m a strong believer that hormones shape our lives in more ways than people tend to realise and therefore it was a huge pleasure for me to read this book.

I didn’t know what to expect from the author. Having come from a nursing background, I often find that medical books can be either too difficult for general public to relate to or sometimes they’re disappointing for professionals due to lack of medical jargon and science.

This books genuinely delivers on all fronts. I loved how thoroughly Max chose to illustrate the power of our endocrine system. I enjoyed his decision to discuss hormonal process in relation to human life (from conception to old age) as opposed to focusing on each bodily system separately. I thought it was a clever touch and a very approachable way to engage a wider audience.

Brilliant book, I would strongly recommend it.