A celebratory martini. A handful of potato chips. A lungful of second-hand smoke. You may call it a night on the town, but your body's cleaning crews will be working the late shift. Think of your body as a spectacularly engineered waste-management facility. Your circulatory system, lymphatic system, liver, colon and urogenital tract work doggedly to keep you healthy by breaking down and whooshing out junk food, bacteria, viruses and toxins, and too much alcohol. And while clean living would be the best way to help the crews out, you don't have to swear off fun to lend a hand.

Here are some alternatives:
Flushing out your circulatory system
Your veins and arteries represent your cardiovascular super highway, pumping about five litres of blood through your body every minute. But because many of us still love fat-laden ice cream and hot chips or refuse to get off our backsides, there's also artery-clogging sludge in there, such as LDL or "bad" cholesterol; homocysteine, an amino acid linked to heart disease; and triglycerides, fats that build up if you don't burn them off with exercise. Certain crud busters can help keep problems in your blood system to a minimum.

Lipoprotein lipase. This body enzyme cleans the arteries by breaking down triglycerides, says Dr Ruth McPherson, director of the Lipid Clinic at the University of Ottawa Heart Institute in Canada. Boost it with exercise such as a brisk 30-minute walk, five to six times a week. Most important, exercise burns off excess fat. "Fatty acids and cholesterol give our muscles energy to burn," says Dr William Kraus, a cardiologist at Duke University in Durham, US. The problem is, we're not using our muscles enough. "It's like storing up tons of coal without ever putting it in the furnace. You could wind up with an environmental hazard."

HDL cholesterol – your good cholesterol – hoovers up triglycerides and bad cholesterol, then dumps them off at your liver for processing and excretion. The more HDL you have, the lower your risk of heart disease. Research suggests you can increase HDL with a daily glass of wine &ndsh; but no more than one glass, otherwise you'll raise your triglycerides. Other HDL boosters include exercise (again) and niacin, a nutrient found in meat, nuts and whole grains.

Then there's folate. From oranges, it helps your body clean up excess homocysteine, says Jim Joseph, a neuroscientist at Tufts University in Boston. And preliminary animal research from Japan has found that a diet rich in hesperidin – a compound also found in oranges – could lower total cholesterol and triglycerides. Fatty acids in walnut and flaxseed oils and cold-water fish such as salmon will also help flush triglycerides from your pipes.

Keeping your lymph on the go
Brimming with disease-fighting white blood cells, plasma and antibodies, lymph bathes your cells and carries away anything foreign or potentially harmful, such as bacteria and viruses, says Kent HayGlass, professor and head of the Department of Immunology at the University of Manitoba, Canada. Your job is to keep it moving for maximum efficiency.

Deep breathing is a simple way to help your immune-system highway, says Ann Louise Gittleman, a nutrition expert. The negative pressure in your chest as you inhale helps push lymph through the body.

A long stretch with your arms out or up also opens your chest cavity for maximum breathing capacity.

A hot and cold shower will also keep your lymph flowing, says Pamela Frank, a naturopathic doctor. Try taking a hot shower for three minutes, then switching the water to cold for one minute and repeating the process twice again.

"The heat causes dilation of the blood vessels, while the cold causes contraction," says Frank, "which creates a pumping action that helps move your lymph." But talk to your doctor first. This treatment isn't for everyone. Walking, jumping or bouncing. Activities such as these, which work muscles and get your heart beating faster, will also do the trick. For optimum lymphatic circulation, Gittleman suggests jumping rope or stepping on a mini-trampoline for 20 minutes, five times a week.

Protecting your liver
Gary Fagan, president of the Canadian Liver Foundation, says our largest internal organ doesn't get proper respect. That's a shame, because while you kick back with a spritzer, your liver is processing an astounding 86 litres of blood every hour, filtering out toxins and producing bile to break down fats.

Keeping an ideal weight can be a potent liver protector, so ask your doctor what is right for you. Being overweight can lead to insulin resistance and elevated blood levels of insulin, which contribute to liver damage, says Dr Eve Roberts, a hepatologist at the Hospital for Sick Children (HSC) in Canada.

Cruciferous vegetables such as Brussels sprout and cabbage help your liver zap excess oestrogen. While oestrogen can do a lot of good, if you're a woman, too much increases your risk of breast cancer. Cruciferous vegetables contain compounds called indole glucosinolates, which boost liver enzymes that can break down excess oestrogen and cut your cancer risk, says Patricia Harper, senior scientist at HSC's Research Institute.

Water and healthy fats also help keep cleansing bile moving. So drink enough water and assist your liver by creating high-quality bile by eating fish, nuts and canola oil, and eggs in moderation. These foods help keep bile gooey, like free-flowing motor oil, says Roberts.

Cleaning up your colon and urogenital tract
If your liver gets no respect, just think what it's like being the butt of all that toilet humour. Your colorectal and urogenital tracts carry on despite the barbs, absorbing nutrients and water from everything you eat and drink, and flushing out bad fats and waste. Fibre – especially the soluble kind in oat bran, fruits and vegetables – stimulates the colon's squeezing action and binds to cholesterol and harmful fats to help sweep them out of your system. To get the recommended 25 to 30 grams a day, gastroenterologist Dr Dan Sadowski suggests eating whole-grain breads, wild rice and lentils, as well as bran cereals with at least six grams of fibre per serving. Unlike antibiotics and antifungal medications, good bacteria such as certain strains of lactobacillus send signals encouraging bad bacteria to stop releasing harmful toxins. "It's a natural way to detoxify the urogenital tract," says Reid.

Try getting lactobacillus from daily servings of sauerkraut or probiotic yoghurt. Reid also recommends natural probiotic capsules.