Is saturated fat bad for you?

[Surreal]

@DSeid

This 2009 science advisory from the American Heart Association reviewed all the evidence for and against the oft repeated claim that more n-6 may be harmful. The conclusion.

The AHA? The Count Chocula people? Seriously?

Wikipedia has a good summary of the actual science:

Omega-6 fatty acid

Some medical research suggests that excessive levels of certain n−6 fatty acids, relative to certain n−3 (Omega-3) fatty acids, may increase the probability of a number of diseases.[3][4][5]

Modern Western diets typically have ratios of n−6 to n−3 in excess of 10 to 1, some as high as 30 to 1. The optimal ratio is thought to be 4 to 1 or lower.[6][7]

Excess n−6 fats interfere with the health benefits of n−3 fats, in part because they compete for the same rate-limiting enzymes. **A high proportion of n−6 to n−3 fat in the diet shifts the physiological state in the tissues toward the pathogenesis of many diseases: prothrombotic, proinflammatory and proconstrictive.[8]**Chronic excessive production of n−6 eicosanoids is associated with heart attacks, thrombotic stroke, arrhythmia, arthritis, osteoporosis, inflammation, mood disorders, obesity, and cancer.[9] Many of the medications used to treat and manage these conditions work by blocking the effects of the potent n−6 fat, arachidonic acid.[10] Many steps in formation and action of n-6 hormones from n-6 arachidonic acid proceed more vigorously than the corresponding competitive steps in formation and action of n-3 hormones from n-3 eicosapentaenoic acid.[11] The COX-1 and COX-2 inhibitor medications, used to treat inflammation and pain, work by preventing the COX enzymes from turning arachidonic acid into inflammatory compounds.[12] (See Cyclooxygenase for more information.) The LOX inhibitor medications often used to treat asthma, work by preventing the LOX enzyme from converting arachidonic acid into the leukotrienes.[13][14] Many of the anti-mania medications used to treat bipolar disorder work by targeting the arachidonic acid cascade in the brain.[15]

A high consumption of omega-6 polyunsaturated fatty acids (PUFAs), which are found in most types of vegetable oil, may increase the likelihood that postmenopausal women will develop breast cancer.[16] Similar effect was observed on prostate cancer.[17] Other “analysis suggested an inverse association between total polyunsaturated fatty acids and breast cancer risk, but individual polyunsaturated fatty acids behaved differently [from each other]. […] a 20:2 derivative of linoleic acid […] was inversely associated with the risk of breast cancer”.[18]

[Surreal]

@DSeid

In particular the evidence from RCTs is that

Did you actually read this? It doesn’t support your claim.

Summary: This review should help to settle any outstanding controversy over the dietary ratio of n-6/n-3 polyunsaturated fatty acids. It reinforces current recommendations to increase the consumption of preformed eicosapentaenoic acid/docosahexaenoic acid in fish, and supports dietary measures to increase and decrease intakes α-linolenic acid and linoleic acid, respectively, to promote the endogenous synthesis of these longer chain n-3 polyunsaturated fatty acids.

[DSeid]

Surreal it is when someone tries to trump the AHA and a complete evidence based review by citing wiki!

Yes, I read it. The portion you are referencing refers to two different n-6 PUFAs: if DHA and EPA (also PUFAs) intake is insufficient the conversion of n-6 into n-3 is maximized by keeping one n-6 PUFA, ALA, higher and another n-6 PUFA, linoleic acid, relatively lower. Not all n-6’s are equal.

Did you read it? Or at least understand what you read?

[Surreal]

Of course I understood it. It’s saying that reducing intake of n-6 linoleic acid is healthy, which is exactly what I’ve been saying throughout this entire thread.

[Surreal]

@DSeid

The portion you are referencing refers to two different n-6 PUFAs: if DHA and EPA (also PUFAs) intake is insufficient the conversion of n-6 into n-3 is maximized by keeping one n-6 PUFA, ALA, higher and another n-6 PUFA, linoleic acid, relatively lower.

Wrong. Alpha-linolenic acid (ALA) is an n-3 PUFA, not an n-6 PUFA.

α-Linolenic acid

[Candyman74]

For some reason I’m reminded of an old Fry & Laurie sketch.

“I heard that too much of it was bad for you.”
“Well, of course it is. That’s what ‘too much’ means - too much. Too much water is bad for you.”

[Goosie]

My doctor told me to stay away from saturated fats, and I told my doctor that I haven’t been near a pool-hall in 10 years!!

[Surreal]

When PUFAs replace SFAs, the evidence from epidemiologic, clinical, and mechanistic studies is consistent in finding that the risk of CHD is reduced. In countries following a Western diet, replacing 1% of energy intake from SFAs with PUFAs has been associated with a 2–3% reduction in the incidence of CHD (13, 17). This figure is probably an underestimate of the benefit …

In addition to the evidence I’ve already presented, a recent analysis of the Sydney Diet Heart Study (an RCT) found that the intervention group that consumed more linoleic acid and less saturated fat actually had higher mortality from all causes, including deaths from cardiovascular disease:

Study raises questions about dietary fats and heart disease guidance

[barbitu8]

@Surreal

In addition to the evidence I’ve already presented, a recent analysis of the Sydney Diet Heart Study (an RCT) found that the intervention group that consumed more linoleic acid and less saturated fat actually had higher mortality from all causes, including deaths from cardiovascular disease:

Study raises questions about dietary fats and heart disease guidance | ScienceDaily

That

[barbitu8]

I was too late in editing. My computer is acting strange and sent the message before I was finished (twice). That study referred to omega-6 in linoleic acid and not to the omega-3 PUFA. It has been known for years that we have been consuming too much 6 and not enough 3. The Wikipedia link states the ratio should be 4:1 or less.

[Michael63129]

As far as saturated fat in dairy goes, this meta-analysis of 15 studies suggests that people with high dairy intake have a lower risk of CVD and diabetes than people with a low intake. In particular, the last study in this table looked at dairy fat only and found a relative risk of just 0.67 for heart attack, which seems counter-intuitive when you look at the amount of saturated fat in dairy, about 2/3 of the total fat, as compared to about 1/3 in meat (i.e twice as much for the same amount of total fat):

Results: From meta-analysis of 15 studies the relative risk of stroke and/or heart disease in subjects with high milk or dairy consumption was 0.84 (95% CI 0.76, 0.93) and 0.79 (0.75, 0.82) respectively, relative to the risk in those with low consumption. Four studies reported incident diabetes as an outcome, and the relative risk in the subjects with the highest intake of milk or diary foods was 0.92 (0.86, 0.97).

Of note also is that high dairy fat intake raises LDL cholesterol (saturated fat also raises HDL cholesterol more than unsaturated fats, in particular, one type raises it more than even omega-3s), but it turns out that LDL cholesterol is more complex than popularly perceived; not all LDL is the same (this article blames carbs, at least simple/refined carbs, for raising the bad type of LDL).

Oddly, this article quotes 11 out of 16 studies as finding that higher dairy fat intake is associated with lower body fat and/or less fat gain over time (“odd” because, again, people often blame saturated fat for weight/fat gain, which is true if you are eating too many calories, but even fruits and vegetables will make you gain weight if you overeat - admittedly, harder to do so with low-caloric density foods, thus the recommendations to eat more of these).

Also, here is another meta-analysis based on 20 studies that found no link between red meat, popularly perceived as being unhealthy (I often see people place it in the same category as junk food), and heart disease and diabetes risk - unless it it processed (nitrites added, which may be why it is bad despite efforts to reduce nitrosamine formation, also linked to a higher cancer risk, especially gastrointestinal cancer).

[Leo_Bloom]

@KneadToKnow

Just don’t try nonfat half-and-half. It’s beneath vile.

I think of that when I see it in the supermarket. It seems like a food paradox, and I’ve never been motivated to try it.

I’ve finally gotten used to skim milk (my wife insists), by treating it like water to quench my thirst. Can’t cook with it for beans.

And she buys fat-free, yuch yoghurt. Which of course has tons of sugar. Fake sugar fat-free better off not eating whatever the hell you want to call that concoction. Worsening diabetes or heart attack? Decisions, decisions.

[barbitu8]

@Leo_Bloom

I think of that when I see it in the supermarket. It seems like a food paradox, and I’ve never been motivated to try it.

I’ve finally gotten used to skim milk (my wife insists), by treating it like water to quench my thirst. Can’t cook with it for beans.

And she buys fat-free, yuch yoghurt. Which of course has tons of sugar. Fake sugar fat-free better off not eating whatever the hell you want to call that concoction. Worsening diabetes or heart attack? Decisions, decisions.

The only sugar yogurt has is lactose unless it is flavored.

[x-ray_vision]

@barbitu8

The only sugar yogurt has is lactose unless it is flavored.

There are other sugars too, such as glucose and galactose.

[Hari_Seldon]

I’m doing this from increasingly fallible memory, but last Saturday, the NY Times had an interesting article on the difference between a “normal diet” and one especially low in saturated fats and high in polyunsaturates. Two groups of men (I think it was all men) with heart disease were given the two diets. That is one group directed to follow their normal diets and the other to follow the low saturated fat/high polyunsaturated diet. At the end of some years, it was determined that the second group had lowered their blood cholesterol quite a bit, but more of them had died. I think the study was too small to really be definitive. They conjectured that the polyunsaturated resulted in inflammation and that is more important than cholesterol in exacerbating heart disease.

Bottom line: they don’t know fuckall about diet. Even slightly overweight people seem to live longer than normal weight ones. I will continue to eat my normal diet.

[Razncain]

I supposed some have already researched the French Paradox. If so, I’d appreciate others opinions on it.

Has SD ever considered a health forum? Not sure if there are any popular MB’s that cover health that is a good source of info, and still doubt any would cover it like the Straight Dope. It seems like there would be enough interest. There is a hell of a lot to sort out, that is for sure.