Diary of a body makeover: Why it's okay to 'eat all that fat'

New research points to inflammation as being the leading cause of heart disease and blocked arteries, and one of the biggest sources of inflammation in our diet comes from sugar.

I've become one of those people. You know the ones ... they lose weight, improve their fitness and health and want to impart their new-found knowledge to anyone who'll listen. Not because I want to blow my own trumpet, you understand. It's just that I get super excited about what it's done for me that I want everyone to know so they can feel better too.

But talking to people about my new way of eating can end up being a fraught conversation as I try to explain why I eat what I eat - or what I don't eat. Or people question how it can be healthy to consume such high levels of fat and so few carbs.

So in the interests of those of you who have questions like those above and for people who, like me, consume a ketogenic diet (ie, high in fat, moderate protein, low carb), today's column is rundown of questions I've been asked often about this way of eating, with answers supplied by nutritionist Sonja Gardiner.

You can't go and exercise without having eaten some carbs (not a question, granted, but rather an actual statement from a colleague).
Depending on the intensity and length of exercise, glycogen stores are likely to be sufficient. Glycogen is our "intermediate" storage of energy, and can be easily accessed when needed. Normally, the body can store enough glycogen to provide energy for around two hours of exercise. When glycogen stores are depleted, the body can still convert fat into glucose, however, this process takes longer and therefore doesn't provide the quick source of energy that glycogen does during intense periods of exercise.

There are a number of studies showing a low carb diet to cause no issues at low to moderate intensity. A recent study in ultra-endurance athletes found that a ketogenic group burned up to 2.3 times more fat in a three-hour low-to-moderate intensity exercise session - which was used for energy. More research is required for higher intensity exercise (and by higher intensity, we're referring to elite athletes). That said, some of my clients have noticed fatigue, tiredness and decreased endurance on a lower carb diet. When that's the case, yes, it can be beneficial to eat some easy-to-digest carbs around 30 minutes before exercise.

Surely it's not healthy to eat all that fat? You'll end up with blocked arteries.
For years we have been led to believe that fat is the leading cause of heart disease. Newer research points to inflammation as being the leading cause of heart disease and atherosclerosis, or blocked arteries, and one of the biggest sources of inflammation in our diet comes from sugar. A recent and very thorough study of more than 40,000 people showed that high sugar intake could quadruple your risk of a heart attack. Sugar is literally deadly; it causes heart attacks, obesity, type 2 diabetes, cancer and dementia.

Not all fats are good for us though. Some fats, in particular highly processed vegetable fats (used in all convenience foods), are pro-inflammatory and should be avoided. Natural, unprocessed fats, whether from plant or animal sources, are best.

Don't you need some carbs for your brain to function properly?
Some parts of the brain can only use glucose for fuel, yes, but the body can make glucose out of protein for use in these parts of the brain. For millions of years we lived without supermarkets and refrigerators with food readily available whenever we needed it. Our bodies are well adapted to go for long periods without food. There are essential requirements for both fat and protein, both of which can be stored at significantly higher capacities than carbs, but our bodies - and brains - can survive quite happily for periods consuming no carbs at all.

Why don't you eat fruit? Fruit is good for you.
Fruit is always going to be the lesser of the treat evils - totally! I often use fruit as a diversion from sugary treats for the kids - I want to teach my kids to eat whole foods that come from the ground and not in a package. It's a no brainer. However, it is still high in sugar, in particular fructose, a type of sugar that our body doesn't tolerate very well. When trying to lose weight, it is important to keep overall carbohydrate consumption down, and while fruit provides an array of nutrients and fibre, it is best to opt for green vegetables which are higher in fibre and lower in carbohydrates, gram for gram.

Won't you get a fatty liver if you eat all that fat?
I hate to use this sad practice to illustrate my point here, but what are ducks or geese destined to end up on someone's plate in the form of foie gras force fed? SUGAR! In the form of corn and starch. Sugar turns on fat production in the liver. Fatty liver is caused by our high intake of sugar and refined white flour, not healthy fats.

Isn't that just the Atkins diet that you're doing?
No. There are some similarities, but while the Atkins diet will produce a ketogenic effect if followed correctly, it is distinctly different in that the Atkins diet was a commercialised diet, which became an industry in itself, with very strict foods allowed and disallowed at certain points.

The ketogenic diet is a concept, not a commercialised diet. There's a different macronutrient ratio goal in keto, although the focus is still on restricting carbohydrates. It offers lots of options and flexibility within certain parameters aimed at helping you achieve ketosis in order to stimulate weight loss and encourage a long-term lower carb intake.
Sonja Gardiner is a Hamilton nutritionist on a mission to bring health, wholeness and happiness back into people's lives. To find out more, see www.sonjagardiner.com.