Calling fast food “high fat” is true, but misleading. Image courtesy of avlxyz.

New research from UC Davis sheds light on how triglycerides induce atherosclerosis—the hardening of artery walls that causes heart disease—particularly in individuals with abdominal obesity. Unfortunately, however, the researchers credit the fat in the fast food meal they used to induce the triglyceride spike, while letting the more likely culprit, orange juice, completely off the hook.

In the study, researchers fed a fast food meal (two breakfast sandwiches, hash browns and orange juice, as noted in the press release) to people with either normal or elevated blood triglycerides. Triglycerides correlate strongly with risk of heart disease and are a better predictor of cardiovascular risk than total or LDL cholesterol.

After eating the horrible meal, triglycerides rose and LDL cholesterol was transported into cells in the artery wall, a process that leads to artery hardening and heart disease. This effect was worsened in the presence of cytokines, which are known to cause inflammation and correlate with a larger waist size.

The implication is that poor diet choices become more dangerous as a person’s metabolic health declines, making good nutrition an even greater priority for people with abdominal obesity.

“The new study shows that eating a common fast food meal can affect inflammatory responses in the blood vessels,” said the lead researcher, Anthony Passerini, and the effect seems to be worse in those with chronic inflammation and larger waists.

But why do they extrapolate and claim that this problem is caused by dietary fat?

The authors describe the fast food meal as “high-fat”, but neglect that it is also high in processed carbohydrates (two buns and hash browns) and fructose, the fruit sugar present in orange juice. Fructose is converted to triglycerides in the liver and is the most effective way to increase triglyceride levels.

Not only is fructose from the orange juice the most likely cause of the triglyceride effect, but it is particularly unlikely the fat had an impact. High-fat, low-carbohydrate diets have been used to treat high triglycerides since the 1960s, even at levels as high as 65% of calories from fat. In the current study the fat in the fast food meal represented only 47% of calories.

Though the fast food meal used by the researchers undoubtedly matches the “typical western diet,” it is unlikely that the fat content is responsible for elevating triglycerides and the risk of heart disease that comes with them.

A better message for people worried about triglycerides: watch your sugar.

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Scientists Understand Heart Disease Better, Still Give Bad Advice 12 June,2013Darya Pino

  • KiltBear

    Thank you for this. I’ll take fat calories over empty sugar calories any day. The only thing is that fat packs a lot more calories. All these things marked “fat free” are just garbage in every way.

  • brent

    Neat article! I am trying to reduce my pop intake because of all the sugar.

  • Rene Sugar

    A sugar (sucrose) molecule is made up of a glucose molecule and a fructose molecule. Sugar is quickly broken down into glucose and fructose after you eat it.

    Fructose leaves your body by being processed by your liver like alcohol. The other cells in your body don’t use it.

    Excess fructose can get turned into uric acid raising your blood pressure or get turned into fat. In large amounts, it can result in non-alcoholic fatty liver disease.

    Arachidonic acid from excess omega-6 fatty acid consumption can, through a series of biochemical reactions, suppress nitric oxide formation causing hypertension.

    UCSF endocrinologist Robert Lustig has a video lecture called “Sugar: The Bitter Truth” that goes into a lot more detail on how fructose is metabolized.

    Sugar is not “empty calories”. The fructose in sugar can do a lot of damage. Using the buzz word “empty” suggests it has no effect which is not true.

    Biochemist William Lands at the NIH has a video lecture online that discusses the effects of too much omega-6 fatty acid consumption (e.g. inflammation, heart disease, arthritis, etc.). While meat is one source, a much more concentrated source is vegetable oils and seed oils. The mayonnaise used on fast food burgers is made from vegetable oil and egg yolks both high in omega-6 fatty acid content and contains more omega-6 fatty acids than the burger itself.

    Besides vegetable and seed oils, there are other concentrated sources of omega-6 fatty acids like peanuts.

    The NIH’s “EFA Education” site has software that lets you calculate the omega-6 fatty acid content of your recipes.

    The linoleic acid in the vegetable oil fast food French fries are deep fried in forms a toxic substance called hydroxy-trans-2-nonenal (HNE) when heated to frying temperatures.

    Acrylamides also form during the deep frying of French fries.

    There are no such things as “empty calories” or “heart healthy” oils.

    Try eliminating vegetable oil, peanuts and added sugar from your diet if you want to lose weight and reduce inflammation and blood pressure.

    The software on the EFA Education site at the NIH can help you figure out the rest.

  • atonbn [at] gmail dot com

    Are researchers certain that ingested fat, as in eggs and fatty meats does not
    end up in your abdomen as 1- abdomen fat?? or 2- arterial cloggers? If so this is a game changer.
    It’s also quite a game changer that fructose plays a role in arterial plaques and perhaps more.

  • David

    So the researchers credit the fat in the fast food for causing the triglyceride spike , but YOU think it’s the orange juice? …That sounds kind of crazy to me.

    Glad I followed the link from your other website, otherwise I would have been lead to believed you had a legitimate/unbiased source for your assertion that juiced fruit is bad without having any idea this was just your own cockamamie conjecture. haha


Darya Pino

Darya Pino is a Ph.D trained scientist, San Francisco foodie, food and health writer and advocate of local, seasonal foods. She shares her unique scientific perspective on health and enthusiasm for delicious foods at her website Summer Tomato. Follow her on Twitter @summertomato.

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