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October 17, 2013 by NATASHA LONGO
Why Low-Fat Diets Make You Fat

Governments here and abroad have been cautioning the public for decades on the dangers of high fat diets. Their claims based on "their science" concluded that it's best to avoid fat because of its extra calories - and saturated fats raise the risk of heart disease. You'll still see this on most food pyramids regulated by government policy on diet and nutrition. However, just as mandated healthcare policies fail at the federal level, so do those related to nutrition. This low-fat mantra has been questioned for years by clinicians and nutritional scientists - not least because it has failed to halt the obesity epidemic. The fact is, contrary to official advice by our diet dictocrats, high-fat diets lower blood sugar, improve blood lipids, and reduce obesity.

High-Fat Diets Have Better Effects on Blood Sugar

One of the problems is that there is consistent inverse association in the percentage of energy coming from fats and sugars. Research published in the journal Critical Reviews in Food Science and Nutrition shows why people find it hard to follow government guidelines to cut their fat and sugar intake at the same time -- a phenomenon known as the sugar-fat seesaw.

That's no surprise as previous studies such as a two-year dietary study published in the journal Diabetologia showed that food with a lot of fat and few carbohydrates has a better effect on blood sugar levels and blood lipids. Despite the increased fat intake with a larger portion of saturated fatty acids, their lipoproteins did not get worse. Quite the contrary -- the HDL, or ‘good’ cholesterol, content increased on the high fat diet.

Research from the Hebrew University of Jerusalem shows that a carefully scheduled high-fat diet can lead to a reduction in body weight and a unique metabolism in which ingested fats are not stored, but rather used for energy at times when no food is available. The results were published in The FASEB Journal under the title "Timed high-fat diet resets circadian metabolism and prevents obesity".

Outdated Understanding of Science

Professor David Lawrence, an expert in nutrition and obesity data analysis, said recently in the journal BMC Medicine that the idea the idea of all calories being equal is flawed and based 'on an outdated understanding of the science'.

Calories from different sources have different effects on the body, with calories from carbohydrates more likely to encourage weight gain.

Calories from different sources have different effects on the body, with calories from carbohydrates more likely to encourage weight gain.

Not only is the calorie theory under attack, but evidence is also emerging to show that lowering fat might not cut heart-disease risk after all.

A major study published in the authoritative New England Journal of Medicine compared the clinical benefits of a conventional low-fat diet with two types of Mediterranean diet, which are naturally considerably higher in fat.

The study had to be stopped early because the heart attack and stroke rate in the Mediterranean options was so much lower it was deemed irresponsible to keep patients on the conventional diet.

Relevance of Glycemic Load

A study led by Cara Ebbeling, PhD, associate director and David Ludwig, MD, director of the New Balance Foundation Obesity Prevention Center Boston Children's Hospital, found diets that reduce the surge in blood sugar after a meal--either low-glycemic index or very-low carbohydrate-may be preferable to a low-fat diet for those trying to achieve lasting weight loss. Furthermore, the study found that the low-glycemic index diet had similar metabolic benefits to the very low-carb diet without negative effects of stress and inflammation as seen by participants consuming the very low-carb diet.

Weight re-gain is often attributed to a decline in motivation or adherence to diet and exercise, but biology also plays an important role. After weight loss, the rate at which people burn calories (known as energy expenditure) decreases, reflecting slower metabolism. Lower energy expenditure adds to the difficulty of weight maintenance and helps explain why people tend to re-gain lost weight.

The study suggests that a low-glycemic load diet is more effective than conventional approaches at burning calories (and keeping energy expenditure) at a higher rate after weight loss. "We've found that, contrary to nutritional dogma, all calories are not created equal," says Ludwig, also director of the Optimal Weight for Life Clinic at Boston Children's Hospital. "Total calories burned plummeted by 300 calories on the low fat diet compared to the low carbohydrate diet, which would equal the number of calories typically burned in an hour of moderate-intensity physical activity," he says.

Though a low-fat diet is traditionally recommended by the U.S. Government and Heart Association, it caused the greatest decrease in energy expenditure, an unhealthy lipid pattern and insulin resistance.

"In addition to the benefits noted in this study, we believe that low-glycemic-index diets are easier to stick to on a day-to-day basis, compared to low-carb and low-fat diets, which many people find limiting," says Ebbeling. "Unlike low-fat and very- low carbohydrate diets, a low-glycemic-index diet doesn't eliminate entire classes of food, likely making it easier to follow and more sustainable."

Some Governments Are Making a U-Turn

Faced with mounting evidence, Swedish dietary experts recently made a dramatic U-turn, recommending a low-carb, rather than low-fat, diet for weight loss.

The bombshell came from the Council on Health Technology Assessment, which advises the Swedish government. Based on a review of 16,000 studies, it said the best sorts of food for losing weight were high fat foods which could include anything oils like olive and coconut.

So the rules are being rewritten: to lose weight, cut down on carbs and eat more fat.

So what, precisely, is behind this new thinking? It comes down to the effect different foods have on your hormones.

The most important of these hormones, and the one that's crucial for weight loss, is insulin.

Insulin is the hormone that controls fat storage. A high-carb diet increases the amount of glucose in the bloodstream, which in turn means you produce more insulin. The more insulin the body produces, the more fat gets stored. When the body is exposed to a high-carb low-fat meal, the pancreas works hard at overshooting the secretion of insulin which then causes the excess to be stored as fat. A low-carb and high-fat diet means less insulin, making it easier to lose weight because less fat is then stored.

More Calories But More Weight Loss

Dramatic new evidence for this has come from a unique experiment conducted by a personal trainer. As Sam Feltham explains: 'My business is helping people to lose weight, and if all calories aren't equal, that could make a real difference.'

A few months ago, Sam upped his intake to a massive 5,000 calories every day. For three weeks he got these calories from a low-fat, high-carb diet; for another three, he ate more fat and cut right back on carbs.

He did exactly the same, moderate exercise regimen each time.

Now, according to the conventional wisdom, the weight gain would be the same on both regimens. After all, a calorie is just a calorie.

In fact, on the low-fat diet Sam stacked on 16lbs around his waist.

But when he ate more fat and cut his carbs, he added just 2.5bs and lost 1in (2.5cm) from his waistline.

'I'm sure I eat more calories than I burn, yet my weight and waist measurement normally remain the same.'

Sam, who survived childhood cancer (Hodgkin's lymphoma), wondered if his usual low-carb diet was the key, and set about his experiment to find out.

For the low-carb, high-fat part of the experiment, Sam got his 5,000 calories from foods such as eggs, mackerel (which is very fatty), steak, green veg and coconut oil, interspersed with three snacks of nuts - walnuts, pecans or almonds (which are naturally high in fat).

While 72 percent of his total calorie intake came from fats, 22 percent came from protein and just 5.9 percent from carbs. Each meal was exactly the same every day.

With the high-carb diet, most of his calories (63 percent) came from carbohydrates, 13 percent from protein, and 22 percent from fat.

He ate garlic bread, low-fat lasagna, crumpets, low-fat yogurts and rice pudding, chocolate muffins and wholewheat bread.

Admittedly the types of fat on his high-fat diet weren't your usual fatty foods, such as cream and butter. And his high-carb diet wasn't exactly 'healthy'.

But the point was not comparing the health benefits of the two, says Sam. 'It was an experiment to test the idea that different foods affect your body's biochemistry differently. 'If it is true that cutting calories is the key to weight loss, then excess calories should put on the same amount of weight whether they come from a “healthy” diet full of fat or a poor diet full of carbs.'

He says he was 'really surprised' at how little weight he put on with the low-carb/high-fat diet, while on the high-carb/low-fat diet his body fat increased from 12.7 percent of his body weight to 16.9 percent.

Degrading Health On Low-Fat High Carb Diets

While Sam's experiment was by no means a scientific one, as well as the weight gain, what was even more striking was what an unhealthy effect the high carbohydrate regimen had on standard markers for heart health.

For when Sam had his blood tested after his three weeks on high carbs, 'the diet effectively gave him metabolic syndrome which is a precursor to heart disease and diabetes.

Particularly worrying was that his triglycerides (fats in his blood) had gone up four times, while his so-called 'good' (HDL) cholesterol had dropped.

What's more, a level of inflammation in his liver had doubled, which is also linked with diabetes and heart disease. "If someone came into my clinic in that state, I'd make it clear they needed to make some serious changes to their diet and start eating a diet low in carbs. I was really surprised that the damaging changes had happened so quickly," stated Dr. Aseem Malhotra, a cardiologist at the Royal Free Hospital in London.

Did the fact that, as a personal trainer, Sam was obviously very fit at the start of his trial make a difference?

"Absolutely," says Dr Malhotra. "It is alarming to think that if a high-carb diet can have that effect on him in three weeks, what is it doing to people who don't exercise and eat like that for years?"

Standard Dietary Advice is Wrong!

"This is a vivid illustration of the fact that the conventional idea of what causes weight gain is back to front," says Dr Malhotra. "We've been told for years that eating fat will make you fat because it contains twice the calories that are in carbohydrates. That is to misunderstand how fat storage works."

Research has already shown that if you are eating a high-carb diet, and so have high levels of insulin, you are likely to have more fat in your blood than someone on a high-fat diet.

"This is what happened to Sam."

Fat Does Not Clog Up Arteries

But doesn't eating extra fat clog up your arteries? No, insists Dr Malhotra. In fact, he says, it's too many carbs that are the problem.

He argues that - as seen with Sam - a high-carb diet tends to lower the good HDL cholesterol that helps keep arteries clear.

At the same time, as glucose from carbs is turned into fat for storage in the body, fatty acids are also produced.

It is this combination of fatty acids and low HDL, not saturated fat, that "clogs your arteries," says Dr Malhotra.

Recent research supports the idea that warning about saturated fat in the diet has probably been a mistake.

"The influence of dietary fats on serum cholesterol has been overstated," say the authors of a review in Advances In Nutrition in May. "The lack of any clear evidence that high-fat foods lead to adverse health effects makes one wonder how they got such a bad name."

Demonizing fat and encouraging people to eat more carbs can be harmful to people with heart disease, says Dr Malhotra. "I see patients who have had a heart attack and are trying to lose weight on a low-fat diet and are puzzled because they are gaining weight."

"When I investigate, it is usually because they are eating lots of low-fat supermarket foods which are also high in carbs such as sugar."

"When I get them eating real foods and not worrying about fat, their weight starts to come down."

Those eating low-carb these days are much more flexible about the amount of fat they get. Research is still needed to sort out the best ratio of carbs to fat.

Western governments have yet to acknowledge the Swedish style U-turn in healthy eating advice. I've personally been on many of these public policy and procurement programs investing hundreds of hours of my time trying to convince officials that food pyramids have to be thrown out the window along with many recommended foods they hold praise to. As soon as these recommendations are forwarded to the highest levels, they are dismissed.

We are spending billions trying to cope with metabolic diseases such as diabetes, cancer and obesity and the emphasis on low-fat diets is only promoting the metabolic pathways which encourage these diseases.

The bottom line is to commit to educating yourself on the healthiest nutritional strategies for your health and not follow any recommendations by government, unless perhaps if you live in Sweden.

Natasha Longo has a master's degree in nutrition and is a certified fitness and nutritional counselor. She has consulted on public health policy and procurement in Canada, Australia, Spain, Ireland, England and Germany.

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