Brigid Sweeney

Your organs produce a slew of natural chemicals that regulate everything from libido to chocolate cravings. Learn to harness their positive powers.


Thyroxine and triiodothyronine

They act as your body’s internal thermostat and they’re also major players in regulating metabolism and energy levels. But factors like chronic stress, nutritional deficiencies and inflammation can throw these hormones out of whack.

“Overactivity can lead to palpitations, heat intolerance, diarrhoea and anxiety,” says Dr Jennifer Wong, endocrinologist and deputy director of diabetes at Dandenong Hospital, Vic.

“Underactivity can lead to constipation, depression and weight gain.” Either way, not much fun.

BALANCE IT OUT Stress less, eat better... You know the drill. However, for more severe cases, medication is best.

“But iodine can also exacerbate some conditions and large doses should be avoided,” says Dr Wong.

Environmental toxins like bisphenol A (BPA) – the nasty chemical in certain plastics – can also disrupt thyroid function, according to research from the University of Michigan, US. Be sure to research plastic products before you buy them, and also remember that BPA can lurk in sneaky places like plastic takeaway coffee cup lids (so toss ’em, don’t sip through them).

Heavy metals like mercury – often found in big fish like shark and tuna – may also cause a thyroid imbalance.



Whenever you’re in danger – or just really frazzled – your hypothalamus (part of your brain linking the nervous and endocrine systems) shoots cortisol, a stress hormone, into your bloodstream. It quickens your heartbeat, feeds your brain extra oxygen and unleashes energy from fat and glucose stores – all good things, in a pinch.

“It’s a feedback system so if you’re constantly stressed, you’ll have high levels of cortisol,” says endocrinologist Professor Lesley Campbell.

Long-term elevated levels can increase the risk of obesity, diabetes and heart disease.

BALANCE IT OUT Just three hours a week of cardio or strength training will considerably reduce cortisol levels, especially if you keep workouts short and sweaty.

“When you exercise for more than 40 minutes, cortisol starts to rise again,” says Dr Natasha Turner, author of The Hormone Diet. Yep, we’re telling you to keep those gym sessions short – go for intense, interval-based routines for 30 minutes in total.


Come sunset, your brain’s pineal gland starts to secrete the sleep-promoting hormone. (Levels peak in the hours of the morning you used to come home after a Friday night out). It needs total darkness to work: real or artificial light can mess with production, which is bad news, because melatonin also counteracts stress and acts as a free-radical-busting antioxidant. Low melatonin levels have also been linked to obesity, diabetes and cancer.

BALANCE IT OUT If your bedroom isn’t pitch-black you’re not optimising your melatonin output. Researchers from Harvard Medical School, US, found that electrical light at bedtime suppresses melatonin levels.

Banish light-emitting electronic devices (mobiles, laptops, TVs) and try an eye mask or invest in black-out blinds.

And go commando in bed: scientists in Japan found that wearing tight clothing like a bra can curb melatonin production by up to 60 per cent. You can also try snacking on a few melatonin-rich cherries before bedtime.


Your brain releases the so-called love hormone whenever you touch someone (a lover, a friend). High levels can bolster sex drive, fight stress, lower blood pressure and heighten feelings of trust.

A Canadian study published in the Journal of Psychopharmacology found that people felt more extroverted under the effects of the hormone. Oestrogen greatly enhances oxytocin’s effects, making women bond more intensely after sex, and making even a normal touch a turn-on during ovulation.

BALANCE IT OUT Snuggling – with your partner or even a pet – can trigger a dose of oxytocin. So can just thinking about touch: in one study from the University of North Carolina, US, oxytocin levels were lifted in women who daydreamed about their partner. But the best way to trigger a love rush? Don’t dream about it, do it! Oxytocin levels skyrocket during and after orgasm. Just one more good reason...


Oestrogen and progesterone

As your ovaries ramp up the production of one female sex hormone, they simultaneously slow down production of the other; it’s a vital seesaw that keeps your reproductive system running (and, sadly, ushers in PMS). But the happy partnership can be compromised by weight gain, chronic stress or exposure to toxic chemicals like BPA.

According to Professor Henry Burger, endocrinologist and founding director at Jean Hailes for Women’s Health, a decline in oestrogen levels in the last week of your cycle can contribute to premenstrual symptoms like irritability and also migraines. Super.

BALANCE IT OUT “The pill provides fairly stable levels of oestrogen and a synthetic progesterone,” says Professor Burger. You can also prevent an imbalance by eating an organic, whole-food diet and maintaining a healthy weight (excess body fat secretes extra oestrogen).

Cut back on processed junk and eat more foods like kale, spinach, oranges and brown rice. And vegetables such as cauliflower and broccoli are also known to regulate oestrogen levels.


While your ovaries and adrenal glands churn out just 10 per cent of the testosterone that blokes have, the hormone plays the same role in any body: it pumps up sexual desire, muscle strength, bone density and metabolism. Too little can leave you sluggish and depressed, but too much can “cause features of masculinisation like pimples and excess hair on the face, lower abdomen and lower back,” says Professor Burger.

BALANCE IT OUT Enter the pill. Again. “Some have a synthetic progesterone, an anti-male hormone,” Professor Burger says. Some female-specific conditions like polycystic ovary syndrome, can cause big testosterone spikes.


Leptin and ghrelin

Ghrelin, produced in your stomach and pancreas, is the hormone that’s responsible for making you feel hungry. Leptin, secreted by fat cells, suppresses your appetite when you’re up to pussy’s bow. Professor Campbell reckons leptin is most effective as a long-term regulator of your body’s fat stores.

“The more fat in your body, the more leptin produced.” Problem is, over time, the fatter you are, the more immune you become to leptin’s effect.

BALANCE IT OUT Increase your amount of “purposeful activity,” says Professor Campbell. “There has been a radical change in [human] exercise and access to food; you should try and recreate what your body was designed for.”


Often called the feelgood hormone, a UK study published in the journal Biological Psychiatry found it also plays a part in how your brain regulates anger.

BALANCE IT OUT Your body needs carbs to make serotonin, which means a low-carb diet can lead to a hormonal dip (and rise in crap moods). Carbs equals happy? We like.

You also need the amino acid tryptophan to make serotonin; get it in foods like yoghurt and bananas, says Dr Susan Kleiner, author of The Good Mood Diet. The perfect excuse for a brekkie smoothie (or some cheeky banana bread), we say.