Carole Hungerford might be a GP, but she is not a fan of the way the business of medicine works. Not even close. ''Mainstream medicine is run by the drug companies. Doctors are driven by the pharmaceutical industry,'' she says. ''There's a renegade group of us where we try to understand that good health isn't about how many clever pills the drug manufacturers can make for us.''
Hungerford acknowledges the importance of medicine, but her focus is on putting things right before people need it, and that starts with the soil in which we grow food. She is keynote speaker at a seminar for GPs, Are You What You Eat? being held at the Mulloon Creek Natural Farm near Bungendore on October 6, a setting chosen to match the theme of the event - the link between soil, food and health. The public is invited to the dinner that night prepared by Janet Jeffs, when the speakers will hold a question and answer session.
Hungerford believes mineral and vitamin deficiencies play a key role in many health problems. She points to pre-eclampsia in pregnancy, a dangerous spike in blood pressure, which she suggests is linked to magnesium deficiency. Australian soils are low in magnesium and Hungerford recommends magnesium to pregnant women, and to patients with high blood pressure, preeclampsia, anxiety disorders, and chronic fatigue syndrome. ''A healthy woman on a good diet shouldn't be getting eclampsia.''
Selenium is also missing from Australian soils, and Hungerford refers to a study by Professor of oncology at Flinders University Graeme Young suggesting selenium supplementation could dramatically cut the risk of bowel cancer. Hungerford says such findings never get the funding necessary for large randomised controlled trials, because ''no drug company is going to fund a study on something so cheap and that they can't make money out of''.
''Mainstream medicine is run by the drug companies and it's only the drug companies that seem to be able to find the money to get the mega trials,'' she says.
Hungerford, who has GP practices in Sydney and Bathurst, where her husband runs an organic farm, and is author of Good Health in the 21st Century: A family doctor's unconventional guide, is vocal on the need to improve the health of soils. In the meantime, she takes supplements - selenium, zinc, fish oil, magnesium, vitamin D (she believes more people die of vitamin D deficiency by a factor of 10 than of melanoma), and a multi vitamin. ''If we don't clean up our act, clean up our environment and start eating clean foods, we're stuffed,'' she says. ''If you need any evidence at all that we've got something badly wrong in our paradigm, the sperm count of men is falling at a geometrical rate; it is scary.''
The conference is organised by the Mulloon Institute, whose general manager, Elisabetta Faenza, says GPs fall into two camps - those who think diet has a minimal impact and those who are convinced of its importance. She too, stresses that ''you can't fix a car accident with diet'' and medical intervention is one of the hallmarks of increased longevity, but she says many chronic conditions are less successfully treated with medicine. Diet and lifestyle more generally have an important role, she says, in arthritis, type 2 diabetes, autism, asthma, heart disease and cancer.
Many of the speakers agree that health people start with healthy soil. But while Hungerford turns to supplements where soil is deficient, Faenza says unless the body recognises a supplement as food, it is little use. ''If our food was better we wouldn't need to supplement, we are designed to get nutrients from food and sunshine and water,'' she says.
You could do a lot worse than look at what your ancestors ate. Not your grandparents. Much further back. Professor Neil Mann, head of food science at RMIT, studies the hunter-gatherer diet before agriculture about 10,000 years ago, which began the switch from wild, foraged plants and meat, to grains.
''Evidence shows we got smaller and unhealthier,'' Mann says. ''The hunter-gatherer diet suited us. Living on [farmed grains] didn't suit us. Tooth decay began because starch turns to sugar in the mouth. People had all sorts of vitamin and mineral deficiencies because they weren't hunting and gathering a wide range of foods any more.''
The so-called ''paleo diet'' is big in cyberspace, proponents advocating versions of a return to meat and fruits and greens, and avoiding grains. But Mann wants nothing of ''fad diets'': ''Anything I say is based on research,'' he says. ''I'm not a fad dieter and I really get pissed off with people taking our paleo research and putting it into something they make money out of.''
Mann says grains virtually didn't exist before agriculture. People ate wild grasses, plants and berries for vitamins and minerals, and meat and fish for energy and protein. Now, our diet diet now is overwhelmingly dominated by starchy grains, predominantly made up of carbohydrates, especially high glycaemic index carbs.
Mann has had success with experiments on ''paleolithic'' style diets that eliminate high GI carbs - improving acne in teenage boys in one trial, and improving the blood sugar in type 2 diabetics in another. He says start with a vegan diet, fruits and vegetables, plus minimally processed wholegrain, and lean meat, fish and low-fat dairy (in pre-agriculture times, calcium came from wild plants). People wrongly assume meat is the main source of fat in their diet, but in fact it comes from pastries and biscuits and other processed food, which contains palm oil. ''They're the real enemy in modern-day society in terms of our food choices,'' Mann says.
Surgeon Prof John Cartmill is a moderate voice on diet. A specialist in bowel cancer, Cartmill is careful about his diet, but that's about as strongly as you could describe it.
''I don't eat specifically to avoid bowel cancer,'' he says. ''If you were really going berserk, you would eat no processed meat, you would have no high temperature cooking of meat, so no barbecue, nothing brown and delicious, you would avoid alcohol, you would exercise - properly exercise - and you would have a body mass index between 19 and 25.''
You would also eat cruciferous vegetables - broccoli, brussels sprouts, cauliflower, bok choy and cabbage. Garlic and fish, and milk. ''But not all of these things are absolutely certain,'' Cartmill says. ''You could eat this way and still get bowel cancer.''
Cartmill, professor of surgery at Macquarie University, draws an analogy with trying to avoid a puncture. If you wanted to be super-careful, you would sweep the road in front of your car - ''crazy and impractical and it's probably much easier to check your tyre pressure from time to time''. Which, in bowel cancer terms, means being tested - the fecal blood test or colonoscopy.
But by the same token, Cartmill says, you wouldn't drive your car across a building site. So don't eat a barbecued steak every day. If you double your fibre intake, you halve the risk of bowel cancer, he says. Eat a high-fibre cereal, or make your own baked beans. He uses a recipe from Stephanie Alexander, which has bacon, one of the things to avoid - but he prefers everything in moderation.
Cartmill calls himself a conservative professional, but he has an open mind on less-mainstream theories like those of Hungerford. He was influenced by reading Hungerford's book - and now takes supplements. But that's personal, not part of his profession.
He does advise his patients to exercise and eat well. He points them to the Food, Nutrition, Physical Activity and the Prevention of Cancer: A global perspective, from the American Institute for Cancer Research.
But he is reluctant to be prescriptive.''People get their pleasure from different places,'' he says. ''I get pleasure from eating, exercise, but people who get pleasure from high-fat, lower-fibre food need to be prepared to keep an eye out for bowel cancer - or take their chances.''
Your chances are about 1 in 20 to 1 in 30, doubled if you have an immediate family member with bowel cancer.
Dr Ross Walker has seen too many diseased hearts to worry about niceties when talking good nutrition. His advice is straightforward and to the point. And fairly unrelenting. It's his way or the highway.
''The big problem with all of us living in modern society is that we take in more calories than we burn off with activity and movement and exercise,'' he says. ''The first principle for all of us is to eat less food. Get rid of unnecessary food during the day. Don't have second helpings, don't have dessert and don't graze, we're not a cow.
''The second principle is get rid of processed, packaged muck that's masquerading as food. So anything that's in a box or a container with a use-by date and it doesn't matter what graffiti is written on the box like 'low fat' or 'no cholesterol', it's typically not good for you.
''Anything from a bakery with pastry on the outside of it is also not good for you. So it's not the meat in meat pies that's killing you, because there's no meat in a meat pie, it's the pastry on the outside. And all these things are full of trans-fats.
''Takeaway food is poison, of course. White death, to me, is sugar, salt, white bread, rice, pasta and potato. These things go straight to the belly and cause significant abdominal obesity.''
Instead, eat three to five serves of vegetables a day. ''A serving is about half a carrot so we're not talking about a huge amount of food. Couple of pieces of fruit a day, but even too much fruit has natural sugars in it and can still contribute to abdominal obesity. I think you should only eat two pieces of wholegrain bread a day. And little bits of meat, fish, dairy, eggs, nuts, olive oil and grains and that's about it. There's your diet.''
Got it? The Sydney medico, who will speak at the Mulloon seminar, is well versed in putting out his message, the author of seven books, with reglar television and radio appearances. His book, Five Stages of Health ''debunks the myths and hype of modern health'', leading to his other big belief - that prevention is better than cure.
''Orthodox doctors, of which I am one, I think, focus too much on that wonderful saying, 'If all you have is a hammer, everything looks like a nail.' And the hammer that we have is the script pad or scalpel. We tend to gloss over the importance of lifestyle modification,'' he says. ''The people who practise good lifestyle principles reduce their risk for all significant diseases by somewhere between 60 and 70 per cent, whereas a drug that reduces your cholesterol might reduce your risk of a heart attack by 20 or 30 per cent, with a potential for a bucket of side effects. So lifestyle principles across the board are much more powerful than anything a doctor can do for you.''
When Walker was in his 20s studying cardiology, he ''just thought it was bizarre that the significantly obese person or the smoker would be coming back for their second lot of bypass surgery. I thought there's got to be a better answer to this.''
That's not to say he doesn't prescribe drugs or send patients to surgery. ''But I also say to them, the acute treatment, the chronic treatment, is changing your attitude to yourself and doing something about that,'' he says.
''I've got two distinct groups of patients. I've got those who follow the advice I give them and they become long-term mates of mine and I see them once a year to ensure they're maintaining the healthy practices and maintaining their medication. And then I've got those who don't follow my advice and whittle away bits of their heart and suffer a premature death.''
Walker's top five principles for healthy living:
1. Get down your belly fat.
2. No addictions. You cannot be healthy if you smoke, if you drink too much alcohol. You cannot be healthy if you snort cocaine.
3. Good quality eating and less of it.
4. Have a regular habit of three to five hours a week of some form of testing exercise - exercise that makes you a bit hot and short of breath. So going for a stroll is not good enough.
5. The best drug on the planet is happiness, peace and contentment.
''Life isn't about making some big decision to be healthy,'' he said. ''Life is about making 30, 40, 50 small instantaneous decisions every day like 'I won't eat that biscuit', 'I won't have that extra glass of wine', 'I'll walk up the stairs instead of take the escalators', 'I won't yell at that fool who just cut across the front of me in the traffic'. Those are the decisions that really take us towards better health.''
The link between diet and disease is of particular interest to Peter Gibbs. When called on to diagnose a sick animal, this veterinarian looks first to diet. And he says this is a practice others in medicine can learn from - and the message he will bring to the Mulloon seminar.
''We as practitioners need to look more totally at what people have done and not just whack them on medicine,'' he says. ''Maybe there are alternatives: changing their diet, changing their vitamin and mineral intake and balancing their life that way.''
In animals, Gibbs has observed a kind of innate, instinctive intelligence about what they eat. For instance, he has seen sheep avoiding crops that are high in nitrate because this substance can cause blood oxygen problems. ''They won't eat things that are poisonous to them unless they have to.''
Likewise, he finds animals can be counted on to choose foods to counteract deficiencies. ''You'll see horses and cattle, if they don't have enough fibre in their diet they'll go eating bark off trees. In a paddock if you've got cattle or sheep and you put out a bale of hay and they really get stuck into that bale of hay you know they really need roughage.''
He believes humans have lost the instinctive ability to select the right sorts of foods for themselves. For him, diagnosis could take the form of simply looking around a landscape: dandelions could cause nerve damage in horses, a particular clover could bring about weak muscles in lambs, a lack of selenium could give cattle reproductive problems.
Microbiologist and immunologist Dr James Chin believes diet can play a role in improving the outlook for children with autistic spectrum disorders.
He suggests, for instance, the importance of folate. This is a B-group vitamin essential for healthy fetal development and preventing defects such as spina bifida if taken before conception and during pregnancy. However, Chin proposes that mothers continue to take the supplement after they give birth, so the baby doesn't suffer a sudden deprivation, saying it could help in tackling autistic spectrum disorders.
Chin also recommends amino acid supplementation, such as tryptophan. Amino acids play an important role in shaping the ability of individuals to express feelings or moods.
''One of the principal problems associated with autistic spectrum disorders is speech and coordination. They have problems with cognitive functionality. So they can't look you in the eye, they tend to be easily distracted, they tend to have a lot of irritable movement. And that is because the neurons in the brain are not firing and connecting in the right order,'' he says.
The best sources of tryptophan are foods such as oats, bananas, dates, milk, cottage cheese, meat, fish, turkey, and peanuts, according to vitamins and health supplements guides.
Chin says in the past year he has seen six mothers who have given their autistic spectrum children amino acid supplementation and found ''significant improvement in stabilising the temperament of the children. They become less irritable and can you look you in the eye. This is after only a small period of two weeks.''
''Nutrition is something most GPs don't pay too much attention to, especially with ASD kids. We found nutrition really helps. Then, of course, antioxidants also play a very important role because the brain has a constant build-up of toxins.''
Chin also points to work recently shown on the ABC's Four Corners program examining the possible links between harmful bacteria in a child's gut and ASD.
Chin, who has done extensive research in gut health, believes supplements of probiotics can help.
>>Are You What You Eat? is on October 6, dinner starts at 5.30pm, $130, themullooninstitute.org/courses-events/food-the-art-of-health