Who would have thought a simple handshake could save a life? When restauranteur Mark Gurrieri shook hands with a diner at his family's restaurant in London's Canary Wharf, he didn't expect a clinical diagnosis. But the customer was Dr Chris Britt and alarm bells rang when the GP noticed his host's particularly "fleshy" hand. Britt suspected a tumour in Gurrieri's pituitary gland was causing over-production of human growth hormone, leading to an increase in soft tissue deposits in the hands. The diagnosis was confirmed and the tumour successfully removed. All thanks to a handshake. The lesson is that however innocuous your symptoms, they could be a life-saving early warning. This DIY guide could help you to spot problems before it's too late.

Pain in your foot... it could be a slipped disc

Assuming it's not caused by dropping a dumbbell on your foot, sharp foot pain could be down to a herniated or prolapsed disc, says Dirk Laubscher, director of London's The Back Clinic. "Pain is usually worse in the morning and aggravated by sitting," Laubscher says. "It's commonly missed as a disc problem because there's no back pain." But it won't go away. "Unchecked it will put increasing pressure on the sciatic nerve, which can lead to loss of bladder function and invalidity."

Act now "Lie on your stomach and do 10 gentle cobra poses [arching your back up and slowly straightening your arms, but keeping your hips on the floor]," says Laubscher. If the pain eases you probably have a slipped disc since these extensions relieve the pressure. "Do cobra poses every hour until you can get to a physio."

Back pain... it could be a kidney stone

You feel a sharp pain between your ribs and hip, but "because it's often inconsistent, you may put it down to excessive lifting at first", says Dr Sneh Khemka, associate medical director of health insurance fund Bupa. It may spell worse news than a postponed date with the bar-bell, though. "One in 10 men get kidney stones," says Khemka. "Untreated, they can block urine flow, making your kidney swell. The pain can eventually become so severe it's been described as the closest a man can get to childbirth." Which is a little too much "empathy" for our liking.

Act now "If the pain returns or moves into your groin, see your GP," says Khemka. Treatment varies from non-invasive sound waves to having a tube inserted somewhere sensitive. You can keep stones at bay with 45 minutes of cardio exercise three times a week, according to US research in Medical News Today. "You should also drink 2.5 litres of water a day to prevent stones," says Khemka.

Diarrhoea... it could be an overactive thyroid

The tear-jerking tryst with your U-bend is bad enough, but a small number of Aussie men will experience this serious hormonal malfunction. Left untreated, the form that most commonly affects young men - Graves' disease - can debilitate muscles and make your hair drop out. "It can also lead to severe vision problems," says Mark Vanderpump, consultant endocrinologist at the Royal Free Hospital in London. "Symptoms include severe bouts of diarrhoea along with dramatic weight loss despite having a healthy appetite."

Act now Maybe those oysters didn't taste right, but "if the diarrhoea lasts several days, coupled with poor sleep or intolerance of heat, it's likely you have a thyroid problem so see your GP for blood tests," says Vanderpump.

Leg pain...it could be heart disease

"Leg pain when you're walking or running is a common symptom of cardiovascular disease," says Dr James Stanley of the University of Michigan Cardiovascular Centre in the US. "If the pain stops when you stop, but gets worse when carrying weight, or walking fast then it's probably an early warning that you're at high risk for heart attack or stroke as the arteries supplying the lower limbs narrow."

Act now If you're getting leg aches and particularly if your dad had heart problems, have your GP check your cholesterol and blood pressure. You may be referred for an ankle brachial index to measure blood pressure in your legs.

Erectile dysfunction... it could be Parkinson's

As if going soft wasn't hard enough to swallow, Harvard University research recently found that men who reported erectile dysfunction were almost four times more likely to develop Parkinson's disease in later life.

Act now There's no known way to prevent the disease, though recent research by neurologists at the Mayo Clinic in the US suggests that developing drugs to mimic a protective gene variation could be the key. Don't panic, though. While around one million Australian men are estimated to have regular soft moments, it's more likely to be caused by stress, smoking, alcohol or injury than Parkinson's.

Unsteady on your feet... it could be a tick

Feeling as though you've come down with the flu despite the blazing sun outside? If you're on the eastern seaboard of Australia, and have been enjoying some al fresco summer loving, you may have just picked up an unwanted guest in the form of a paralysis tick. These pesky arachnids drop onto any passing hot-blooded creature and burrow into the darkest, dampest parts of their anatomy - yep, you've guessed it, you may need help checking out all of your nooks and crannies for this one .

Act now If you do find a tick, you'll want to get it out as soon as possible. Use a pair of fine-pointed tweezers to grab the creature close to the skin and, gently and steadily, pull it out. Don't douse the tick with methylated spirits or anything else, NSW Health advises. The chemical onslaught will just stimulate the animal to inject more toxins into your bloodstream.

Bad breath... it could be lung disease

Don't just blame last night's garlic - bad breath could signal a host of problems that Tic Tacs won't fix. "Lung disease, asthma and cystic fibrosis all cause highly acidic breath," says University of Virginia researcher Dr John Hunt. "And the more acidic the breath, the more severe the condition." American Dental Association data found that, while 90 per cent of cases of bad breath were down to hygiene and gums, the other 10 per cent were linked to systematic conditions like lung disease, abscesses and even liver failure.

Act now See your dentist to rule out the likely causes: dry mouth, sinus infection, gum disease or smoking. "They can also spot signs of mouth cancer," says Dr Nigel Carter, chief executive of the British Dental Health Foundation. "Early detection increases your survival chances from 50 per cent to 90 per cent." If the dentist suspects your emissions may have a hidden cause - like lung disease - they'll refer you to your GP who'll send you for tests to measure your breath's acidity. If you get the all clear, you'll just have to head to the nearest Tic Tac retailer.