Monday, March 3, 2014

Wanna avoid a muffin top? Choose the right muffins!

years of dedicated saturated fat consumption at work here
photo: Syonix
"In conclusion, overeating [saturated fat] promotes hepatic and visceral fat storage whereas excess energy from [polyunsaturated fat] may instead promote lean tissue in healthy humans."

This is how a recent scientific paper abstract concludes. Swedish researchers found that eating more saturated fat led to gaining more fat, and eating more polyunsaturated fat led to gaining more lean muscle.

That is powerful information for athletes and anyone interested in losing weight.

How did they discover this?

Here's how the researchers discovered this:

— 39 young adult volunteers of normal weight added relatively high-fat muffins to their normal diet (not bad work!) for 7 weeks in order to gain weight. And they did gain weight.

— The muffins were all the same, except the type of oil used: one group ate muffins with sunflower oil (polyunsaturated fat), and the other ate muffins with palm oil (saturated fat).

— The researchers measured the amount and distribution of body fat on each participant before and after the weight gain.

— The participants who ate saturated fat (can we call it "SF"?) muffins gained more total body fat than the group that ate polyunsaturated fat ("PUF") muffins. The SF group also developed substantially more fat around their internal organs (which is associated with developing type-2 diabetes) than the PUF group.

— What was surprising was that although the PUF group gained weight, much more of it was in muscle mass than fat. Both results call out to people in most developed countries, who tend to gain weight over time, rather than lose it. And they tend to gain it as more fat, not more muscle (unless their midlife crisis leads them to start doing triathlons, etc!)

the right stuff, if you choose unsaturated oil
photo: ChristinaTurtle

The location of the fat inside us matters. Most of our fat is stored subcutaneously, just beneath the skin. If you can pinch it, it's subcutaneous. Visceral fat, the kind that increased so much from eating more SF muffins, is stored inside your abdominal wall and around your internal organs. You can't reach it, but as it grows, so does your waistline (consult the beach bunnies in the photo above). Visceral fat "seems to contribute to a number of disturbances in metabolism", says author Dr. Ulf Risérus, such as diabetes and cardiovascular disease.

this was not the diet that
encouraged fat storage
This new evidence that the types of fats we eat affect not only our risk of heart disease and type-2 diabetes but also where (liver and intestines) and how fat is stored in our bodies is a big deal. It's worth a read.

So why on earth did our ancestors start storing fat in their bellies? Fat releases energy slowly, and we may have evolved needing to eat well to generate and hold onto fat to burn as energy during lean times, whether they were drought in warm places or winter in cold places.

This mattered back then (as it still matters now in areas of the world with hunger and starvation) more than it does now for much of the world's population.

olive oil: a (happy?) monounsaturated fat,
stays liquid in cool temperatures
The paper, which was published in the professional journal Diabetes, makes a really strong health case for lowering your intake of solid fats.

In other words, if you are looking to gain muscle mass and avoid gaining belly fat, you might want to eat more plant oils, nuts, and fish instead of red meat, dairy, and processed foods. You may have heard this before (and some may disagree).

In fact, the findings will surely generate debate and controversy, so stay tuned, but it's an important step in the continuing saga of what in the world we are supposed to eat to stay healthy.


How do I know which type of fat I'm eating?


If it turns mostly solid when room temperature or colder, it is generally saturated fat. If it's really rich and yummy, it's likely saturated fat...

no trans fat, but a whole lotta saturated fat here
if you can't resist, consume in moderation
image: TrainingTidbits
Most animal fats (those in meat and dairy products), as well as chocolate and several plant oils (coconut oil, palm oil, and cottonseed oil) are all high in saturated fats. Hmmm, I was just eating yogurt as I typed this...oops.

Many of these foods do provide benefits, such as supplying us with protein, minerals, and vitamins. However, according to Harvard Med School, pizza and cheese are the biggest sources of saturated fat in the U.S. diet, but this may be because we eat a lot of pizza!

I thought ice cream might also rear its lovely head in there too.

Chemically, a saturated fat is one with no "double" bonds between the carbon atoms in the fatty acid chain and more hydrogen atoms than an unsaturated fat. It is "saturated" with hydrogen atoms and is higher in energy (calories) than unsaturated fats.

The fatty acid chains with all their H atoms can, apparently, pack together tightly, which is why they stay in solid form at room temps (think butter, lard, or coconut oil).


which do you use? plant oils are recommended
image: Wikipedia, with data from US Dept of Agriculture



I'm just a sweet trans-fatty...acid


Some foods, such as my yogurt, are available in lower-fat versions. The problem with trying to lower our saturated fat intake is that industry creates lower-fat options by adding either more sugar or trans fat to the product.

There are a few natural trans fats in full-fat animal foods, but most are created in an industrial process that adds hydrogen atoms back into liquid vegetable oils (such as the PUF oil above). The result is a partially hydrogenated oil, which allows the product to solidify to a nice texture, and industry likes it because it is cheap and increases a food's stability and shelf life.

image: Testalab
Many processed and pre-made foods contain trans fat, so if you eat them -- chips, candy, cookies, crackers, pre-mixed cake and pancake mixes, pizza dough and pie crusts, some breads and buns, and many fried foods, such as donuts, hard taco shells, French fries, or chicken nuggets -- you are probably getting more trans fat than is considered healthy. Sigh. Microwave popcorn is particularly loaded. Who knew?

Trans fats not only raise our LDL "bad" cholesterol, like saturated fats do, but they also lower our HDL "good" cholesterol, so they do double damage.


Read more:


The original paper on the SF vs PUF oils in the muffins

More science: on the evolutionary importance of fat in our diets (especially for early brain development)

Palm oil is also really destructive, both environmentally and socially, in case you are looking for another reason not to buy it, either in food or in cosmetics.

not a lot of visceral fat here -- must be PUF boys
image: EthnicHealthCourt



Bonus activity, from Harvard Medical School
check your own visceral fat by measuring your waistline (oh boy!)

Apparently, the two are strongly correlated. If your waist is more than 35 in (89 cm) around for women or more than 40 in (102 cm) for men, you are at increased risk of diabetes and other chronic metabolic diseases. Happily, I passed the test. How about you? Here are the instructions!

Gut check

A tape measure is your best home option for keeping tabs on visceral fat. Measure your waistline at the level of the navel — not at the narrowest part of the torso — and always measure in the same place. (According to official guidelines, the bottom of the tape measure should be level with the top of the right hip bone, or ilium — see the illustration — at the point where the ilium intersects a line dropped vertically from the center of the armpit.) Don't suck in your gut or pull the tape tight enough to compress the area. In women, a waist circumference of 35 inches or larger is generally considered a sign of excess visceral fat, but that may not apply if your overall body size is large. Rather than focus on a single reading or absolute cut-off, keep an eye on whether your waist is growing (are your pants getting snug at the waist?). That should give you a good idea of whether you're gaining unhealthy visceral fat.
illustration of how to measure waist


No comments:

Post a Comment