2011 AJCN Astrup Hu Krauss Willett Consensus Saturated Fat CVD

Sep 30, 2011 02:37 PM

The role of reducing intakes of saturated fat in the prevention of cardiovascular disease:

where does the evidence stand in 2010?

meeting held in Copenhagen;  paid for by Dairy Councils.

ABSTRACT    paper in AJCN in 2011

Current dietary recommendations advise reducing the intake of saturated fatty acids (SFAs)

to reduce coronary heart disease (CHD) risk, but recent findings question the role of SFAs.

This expert panel reviewed the evidence and reached the following conclusions: 

the evidence from epidemiologic, clinical, and mechanistic studies is consistent

in finding that the risk of CHD is reduced when SFAs are replaced with polyunsaturated fatty acids (PUFAs).

 In populations who consume a Western diet, 

the replacement of 1% of energy from SFAs with PUFAs lowers LDL cholesterol and

is likely to produce a reduction in CHD incidence of ≥2–3%.

No clear benefit of substituting carbohydrates for SFAs has been shown,

 although there might be a benefit if the carbohydrate is unrefined and has a low glycemic index.

 Insufficient evidence exists to judge the effect on CHD risk of replacing SFAs with MUFAs. 

No clear association between SFA intake relative to refined carbohydrates and the risk of insulin resistance and diabetes has been shown. The effect of diet on a single biomarker is insufficient evidence to assess CHD risk. 

The combination of multiple biomarkers and the use of clinical endpoints could help substantiate the effects on CHD.

Furthermore, the effect of particular foods on CHD cannot be predicted solely by their content of total SFAs because individual SFAs may have different cardiovascular effects and major SFA food sources contain other constituents that could influence CHD risk. Research is needed to clarify the role of SFAs compared with specific forms of carbohydrates in CHD risk and to compare specific foods with appropriate alternatives.

Saturated fatty acids (SFAs)

have played a key role in hypotheses relating diet to the risk of

coronary heart disease (CHD), and early evidence based on animal

studies, international comparisons, and controlled feeding trials

with total cholesterol as the endpoint support a major adverse

effect. Thus, a reduction of SFA intakes has been at the heart of

most dietary recommendations to reduce the risk of CHD...

Key issue is ... what are the SFAs replaced by!!!  (eg trans fats and highly processed SFAs may make it worse);

Does evidence from observation, mechanistic and intervention studies provide a coherent picture of the

effect of SFAs on CHD?

ABSTRACT

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 because

it is based on a single measure of diet in a prospective

analysis and because of the high amount of TFA co-occurring in

some PUFA food sources, such as margarines (rich in TFAs

before the mid-1990s).

The epidemiologic data provide strong evidence

that a high intake of processed meat products, a major source of

SFAs, is associated with an increased risk of CHD (32). There is

no consistent evidence that a higher intake of dairy products is

associated with CHD risk in epidemiologic studies (34), but data

do support the beneficial effects of dairy products on type 2..  page 686

Most epidemiologic studies and several intervention studies

support the benefits of Mediterranean dietary pattern on CVD risk

factors and hard endpoints (18, 37). Notably, the Mediterranean

diet is low in SFAs and high in MUFAs. The data on the benefits

of other dietary patterns, such as traditional Asian diets—which

are very low in SFAs—are mainly derived from ecologic and

cross-sectional studies. However, consistent evidence from epidemiologic

studies and RCTs indicate that long-chain omega-3

(n23) fatty acids are beneficial at preventing CHD

Epidemiologic studies have shown a lower risk of CVD with lower intakes of full-fat

dairy products and fatty red meats and higher intakes of PUFAs

from vegetable fats, which is consistent with strong evidence that

replacing SFAs by PUFAs reduces the risk of CVD (38). The use

of nonhydrogenated vegetable oils (including canola or olive oil

rich in MUFAs) decreases the CVD risk compared with animal

fats. Thus, although the evidence is stronger for PUFAs, indirect

evidence suggests that SFAs could also be replaced with MUFAs

as well as unrefined carbohydrates with a low glycemic index. A

valuable way to communicate the message is to describe the

broad dietary pattern that decreases CVD risk. Note that only

a minority of different populations adhere to a healthy dietary

pattern. A healthy dietary pattern is primarily plant-based and

low in SFAs, but can include lean meats and low-fat dairy

products in small-to-modest amount (from page 687)

2011 AJCN Astrup Hu Krauss Willett Consensus Saturated Fat CVD

Attachments