Our resident diet-guru John Nicholson, author of The Meat Fix: How a Lifetime of Healthy Eating Nearly Killed Me, tells us the simple diet advice that changed his health, and his life, for the better; ignore all diet advice.

I am not a guru. For a start, I just don't have the beard or the flowing orange robes for it. And anyway, John isn't a guru’s name. You need to be called something more exotic such as Maharishi or Rodney if you're going to pull the guru gig off successfully.

However, I was doing an interview about my new book The Meat Fix the other day and the interviewer said, 'Do you see yourself as a kind of food guru.' Me? Of course not.

I’m not that kind of dude and The Meat Fix isn't that kind of food book. I'm not one of those American ‘lifestyle’ types with the shiny, shiny teeth and a sound-bite solution for every ill who wants to tell you how to live. They tend to write books with very long sub titles such as:

‘Don’t Die of Food: Why the food in your fridge is killing you, how it got there and what to do about it before your arse is the size of small planet and has its own gravitational pull’

When I wrote The Meat Fix, which is about how a lifelong diet of healthy eating made me ill and why, I didn't think that people would start to come to me for dietary advice but it has happened a few times already.

I wouldn't mind a doctors wage and I think I look pretty good in a white coat but it’s not a role I feel especially comfortable with. For a start, unlike real doctors, I realise that when it comes to a diet that suits you, that will make you fit, healthy and full of energy, we are all different. Different because we all have a unique genetic heritage, but also, and most importantly, because we arrive at the point when we might want to change how we eat after very different dietary histories. Mine was one of the worst. A super-healthy, low-fat, whole-grain, carbohydrate and soya-based vegetarian diet. Yeah, yeah, I know your medically qualified quack will tell you that this is the diet you should pretty much be aiming towards but they know a lot less than you might think they know. Rather, it is very bad for many for us. Trust me, I’m not a doctor.

So you need to work out what works for you which is why when people ask me what they should eat, I hesitate to give a definitive answer. If I really was a food guru I wouldn't be so equivocal. But one thing I've learned is that one-size-fits-all answers are one of the reasons we in the west ended up with so many issues with food and health, with so many degenerative diseases, allergies, intolerances and weight problems. We've been forced down a prescribed healthy eating menu as some sort of cure all with far too much certainty. No one in charge, no one with any power, seems to want to give way on this. Or at least, not many.

Try going to your doctor and tell them you're eating a lot of animal fat and very few carbohydrates and they'll look over their glasses at you and write 'nutter' on your notes. Actually they won't. They’re more likely to write you a prescription for strong narcotics, such as anti-depressants, before ever thinking to ask you what you’re eating. I know, I’ve been there and seen it happen time after time after time. As I write in the book, doctors only ever did two things for me; made me worse or did nothing at all. In the face of my rampant irritable bowel syndrome, weight gain and increasing decrepitude, they had nothing to offer at all and, worse yet, were sneering about my own research. When they say, ‘did you read that on the internet?’ you know the conversation is not going to end well.

This is doing no one any good. That much is self-evident from the health problems that we see around us every day. What are the medical establishment doing about it? Not much. And what they are doing isn’t working. They seem almost pathologically unable to see the real problems, and compound them with inappropriate advice. It is as though we are repeatedly hitting ourselves in the face with a brick and they are telling us that the consequent nose bleeds are being caused by listening to loud music.

It's been remarkable how many times people I've known for a while have, after reading the book, confessed that they have had their own health problems with issues such as IBS, headaches, food intolerances and more. I never knew. We’d never discussed it, just as I’ never talked about my own problems. You don’t. It’s your problem. Your life. It feels weak to discuss it.

I’ve realised since The Meat Fix was published that so many of us keep these issues to ourselves or we get so used to them that we begin to think it is normal. I know I did. You become accustomed to your moods and your state of mind. You think it is who you are and that it is unchangeable. Not for a second did I think my physical or mental health was so geared by what I put into my mouth. But it was. All of it. And it all changed for the better as soon as I changed my diet.

I think it is only when you read how someone else has suffered and how they have transformed their lives by changing how they eat, that a new light is shed on your own experience. So I've been happy to pass on my experiences and suggest some routes towards better health that worked for me.

Come back next week and I'll get my prescription pad out. I will suggest three dietary changes that transformed my weight, health and quality of life and which have done so for many, many other people too. Actually, that does sound a bit food guru-ish doesn’t it? Do you get tax-relief if you set up your own religion? Hmmm.