The doctor who invented intermittent fasting has revealed five steps to follow for long-term, successful weight loss.

In his new book, The Obesity Code Cookbook, Dr Jason Fung, who lives in Toronto, discusses the idea that obesity is often caused by our hormones, particularly insulin, and offers practical, easy-to-follow advice on how to lose weight for good.

In five steps, he explains how cutting back on sugar, protein and refined grains, while the upping intake of natural fats, fiber and vinegar can lead to a healthier lifestyle.

The book, which is out today, includes more than 90 recipes — including slow-roasted pork shoulder to chia pudding and almond cake — showcases healthy fats, nutrient-dense foods, and low or no carbs, with diet plans to help balance your nutrition and energy requirements with your long-term health objectives.

Here, in an exclusive extract from the new release, Dr Jason Fung reveals his five steps to tackling obesity and shares two recipes....

In his new book, the Obesity Code Cookbook, Dr Jason Fung (pictured), who lives in Toronto, explains the idea that obesity is often cause by our hormones, particularly insulin, and offers practical, easy-to-follow advice on how to lose weight for good.

STEP 1: REDUCE YOUR CONSUMPTION OF ADDED SUGARS

Sugar stimulates insulin secretion, but it is far more sinister than that.

The Obesity Code Cookbook (pictured) by Dr Jason Fung is out now

Sugar is particularly fattening because it increases insulin production both immediately and over the long term.

It is composed of equal amounts of glucose and fructose, and fructose contributes directly to insulin resistance in the liver. Over time, insulin resistance leads to higher insulin levels.

Carbohydrates, such as bread, potatoes, and rice, contain mostly glucose and no fructose.

Therefore, added sugars such as sucrose and high-fructose corn syrup are exceptionally fattening, far in excess of other foods.

Sugar is uniquely fattening because it directly produces insulin resistance.

With no redeeming nutritional qualities, added sugars should be one of the first foods to be eliminated in any diet.

Breakfast foods to help you cut back on sugar OATMEAL: Whole oats and steel-cut oats are a good choice, although they require long cooking times to break down the significant amounts of fiber they contain. Avoid instant oatmeal, which is heavily processed and refined. EGGS: A natural whole food, previously shunned due to cholesterol concerns, eggs can be enjoyed in a variety of ways COFFEE: Due to its high caffeine content, coffee is sometimes considered unhealthy. However, recent research has come to the opposite conclusion, perhaps because coffee is a major source of antioxidants, magnesium, lignans, and chlorogenic acid. TEA: Green tea is naturally much lower in caffeine than coffee, making this drink ideal for those who are sensitive to caffeine's stimulant effects. Polyphenols in green tea may boost metabolism, which can improve fat burning. Furthermore, drinking green tea has been linked BONE BROTH: Virtually every culture's culinary traditions include nutritious and delicious bone broth - bones simmered with vegetables, herbs, and spices for flavoring. The long simmering time (four to forty-eight hours) releases most of the bones' minerals, gelatin, and nutrients. The addition of a small amount of vinegar during cooking helps leach some of the stored minerals. Bone broths are very high in amino acids such as proline, arginine, and glycine, as well as minerals such as calcium, magnesium, and phosphorus. Advertisement

STEP TWO: REDUCE YOUR CONSUMPTION OF FINE GRAINS

Refined grains such as white flour stimulate insulin to a greater degree than virtually any other food.

If you reduce your consumption of flour and refined grains, you will substantially improve your weight-loss potential.

White flour, being nutritionally bankrupt, can be safely reduced or even eliminated from your diet.

Enriched white flours have had all their nutrients stripped out during processing and added back later for a veneer of healthiness.

Whole wheat and whole-grain grains and flours are a minimal improvement over white flour because they contain more vitamins and fiber, which help protect against insulin spikes.

Carbohydrates should be enjoyed in their natural, whole, unprocessed form. Many traditional diets built around carbohydrates cause neither poor health nor obesity.

Some great alternatives to refined grains are seeds and legumes including... QUINOA: Technically a seed but often used as a grain, quinoa has been referred to as 'the mother of all grains.' Quinoa is very high in fiber, protein, and vitamins. In addition, it has a low glycemic index and contains plenty of antioxidants, such as quercetin and kaempferol, that are believed to be anti-inflammatory. Dishes like quinoa (pictured) are great alternatives to fine grains, Dr Fung says CHIA SEEDS: These ancient seeds are native to South and Central America and have been dated to the Aztecs and Mayans. Their name is derived from the ancient Mayan word for strength. Chia seeds, regardless of color, are high in fiber, vitamins, minerals, omega 3, proteins, and antioxidants. BEANS: Dried beans and peas are a versatile, fiber-rich carbohydrate staple of many traditional diets and an extremely good source of protein. They come in a wide range of colors, flavors, and textures, from green lentils to black-eyed peas, and red kidney beans to dark brown chickpeas. Canned beans are also great, but be sure to rinse them well before using them Advertisement

Following a Mediterranean diet, including lots of olive oil, is a healthy choice. Dr Fung says

Good natural fats to eat OLIVE OIL: The Mediterranean diet, widely acknowledged as a healthy diet, is high in oleic acid, one of the monounsaturated fats contained in olive oil. Olive oil contains large amounts of antioxidants, including polyphenols and oleocanthal, which has anti-inflammatory properties. It is purported to reduce inflammation, lower cholesterol, decrease blood clotting, and reduce blood pressure. Together, these potential properties may reduce the overall risk of cardiovascular disease, including heart attacks and strokes. NUTS: Prominent in the Mediterranean diet but long shunned for their high fat content, nuts are now recognized as offering significant health benefits. In addition to providing healthy fats, they are naturally high in fiber and low in carbohydrates. They may be enjoyed raw or simply toasted, but avoid those with added sugars, like honey-toasted nuts. Walnuts, in particular, are high in omega 3 fatty acids, which may be beneficial for heart health. Nut milks without added sugars are also delicious. FULL-FAT DAIRY PRODUCTS: Milk, cream, yogurt, and cheese are delicious and can be enjoyed without concern about fattening effects. A review of twenty-nine randomized control trials showed neither a fat-gaining nor fat-reducing effect from their consumption. Full-fat dairy is associated with a 62 percent lower risk of type 2 diabetes. Choose whole-fat dairy products, and raw or organic if you prefer. All milks, including sheep's and goat's milks, are healthy. AVOCADOS: This fruit has been recently recognized as a very healthy and delicious addition to any diet. High in vitamins and particularly high in potassium, the avocado is unique among fruits for being very low in carbohydrates and high in the monounsaturated fat oleic acid. Furthermore, it is very high in both soluble and insoluble fiber. Advertisement

STEP THREE: MODERATE YOUR PROTEIN CONSUMPTION

In contrast to refined grains, food sources of protein such as meats and poultry, seafood, eggs, dairy products, nuts and seeds, and legumes cannot and should not be eliminated from your diet.

But it is not advisable to eat a very high-protein diet, which is often overly reliant on egg whites, very lean meats, or processed proteins such as shakes and supplements.

Instead, moderate the amount of protein in your diet to 20 to 30 percent of your total calories and aim for a variety of sources.

Excessively high-protein diets can lower insulin but are often expensive to maintain and allow relatively few food choices.

STEP FOUR: INCREASE YOUR CONSUMPTION OF NATURAL FATS

Of the three major macronutrients (carbohydrates, proteins, and fats), dietary fat is the least likely to stimulate insulin.

Thus, dietary fat is not inherently fattening but rather potentially protective. And it adds flavor to any meal.

The key is to strive for a higher proportion of natural unprocessed fats, including olive oil, butter, coconut oil, beef tallow, and leaf lard.

Avoid highly processed vegetable oils, including nut and seed oils, which are high in inflammatory omega 6 fatty acids and may have detrimental health effects.

STEP FIVE: INCREASE YOUR CONSUMPTION OF FIBRE AND VINEGAR

Fiber can reduce the insulin-stimulating effects of carbohydrates, making it one of the main protective factors against obesity.

The average North American diet falls far short of recommended daily intake levels, however, because fiber is often removed during processing.

Natural whole foods such as fruits, berries, vegetables, whole grains, flax seeds, chia seeds, beans, nuts, oatmeal, and pumpkin seeds provide ample fiber.

DR FUNG'S RECIPE FOR SHAKSHUKA From the culinary traditions of Israel and North Africa, this thick, quick, spicy tomato sauce makes a perfect braise for eggs. It’s an aromatic feast, good to eat at any time of day. The feta cheese provides enough fat to keep you feeling satisfied for hours. From the culinary traditions of Israel and North Africa, this thick, quick, spicy tomato sauce makes a perfect braise for eggs. It’s an aromatic feast, good to eat at any time of day. The feta cheese provides enough fat to keep you feeling satisfied for hours Makes 4 servings 2 yellow onions

2 red bell peppers

4 garlic cloves

3 Tbsp olive oil

1 tsp ground cumin

1 tsp cayenne pepper

2 Tbsp tomato paste

1 can (28 oz/796 mL) whole tomatoes (with juice reserved)

8 eggs

4 sprigs fresh coriander

1 bunch flat-leaf parsley

3 oz/80 g creamy feta cheese

Salt and pepper 1. Assemble, prepare, and measure ingredients. Thinly slice onions. Chop bell peppers. Mince garlic. 2. In a wide straight-sided saucepan, heat olive oil over medium heat. Sauté onions and peppers for 5 minutes, or until soft. Add garlic and cook for 1 minute. Season with salt and pepper. Add cumin and cayenne, and stir in tomato paste. Cook for 2–3 minutes, or until tomato paste starts to caramelize. Add tomatoes with their juice. Season again with salt and pepper. 3. Simmer gently (just a few bubbles), uncovered, for 10–15 minutes to reduce liquid. The sauce should be thick enough to hold an indentation from the back of your spoon. 4. Make eight indentations in the sauce and carefully crack a whole egg into each one. (This is easiest to do if you crack each egg into a ramekin and pour it into the sauce.) Season with salt and pepper. Cover and cook for 3 minutes, or until whites are set and yolks are cooked to your liking. 5. Roughly tear cilantro and parsley and scatter over shakshuka. Crumble feta evenly over sauce, avoiding eggs. 6. To serve, divide shakshuka among four bowls, giving everyone two eggs. Advertisement