FAT. We hear a lot about it in relation to health but it can be a confusing subject.
Sure, we know that deep fried food contains a lot of the fat we shouldn't eat, ditto fatty meats. These foods contain saturated fats or "bad" fats.
But then there's polyunsaturated fats, trans fatty acids and the other "goodies" - found in flaxseed oil, oily fish, avocado and so on that we're told we should eat.
Got it? Great, but things start to get even more complicated when scientists delve underneath our skin to find out how different forms of stored fat behave.
Put simply, there is ordinary fat that is stored in our body - the kind that results from eating more kilojoules than we need - and "brown fat"(or brown adipose tissue).
The first one is bad if we don't burn it off; the second one is good.
That's because brown fat is a kind of fat that burns kilojoules much more efficiently than the other lumpy fat that deposits itself on our bottoms, waists and under our skin.
In fact, research has shown that people with more brown fat are likely to stay thinner.
This discovery has led to scientists beavering away in laboratories trying to develop a treatment that would increase a person's brown fat.
Meanwhile, researchers from Joslin Diabetes Centre in Boston and Harvard Medical School have discovered that exercising helps turn this fatty mass into the good fat that burns more kilojoules.
They enrolled mice and men in an intense exercise regime that had the men training on an exercise bicycle for 12 weeks and the mice running on an exercise wheel for 11 days.
What both group of participants experienced was a browning of their subcutaneous white adipose tissue. Researchers then transplanted this trained browner fat into sedentary fat mice to see how the browner fat might affect the way their bodies use glucose.
What they found was that after the transplant the mice had increased glucose tolerance and insulin sensitivity for at least three months.
Scientists say the results show that exercise isn't just good for your muscles, it can have a positive effect on lazy fat too.
Even if you don't lose weight, the study suggests that exercising will still train your fat to be more metabolically active and improve overall metabolism and health.
So if you want to beat bad fat, walk, run, cycle, jog, jump or do anything that scares the heck out of fat that puts you at increased risk of heart disease, diabetes and obesity.
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