vendredi 26 janvier 2018

Another example of an observational study which is no more reliable than the precedent ones.



"Diet and cardiovascular disease

In most cases, cardiovascular diseases don’t occur by accident. Lifestyle has an

important part to play, not only in its occurrence but also in prevention. We all know

the risk factors that we have to avoid – smoking, having a sedentary lifestyle, being

overweight, stress, and so on…But we should also list all the things we can do to

stack the odds in our favour, particularly in terms of healthy eating.

This is shown in the first article based on the work of Hever, reminding us that a

healthy diet should be based on vegetable products, supplemented by a moderate

amount of animal products to provide diversity.

The Spanish team that carried out the SUN study of over 19,000 subjects

demonstrated that those scoring highly on the consumption of vegetables, fruit, fish

and fibre reduced their risk of cardiovascular disease by up to 69%.

To close the demonstration, the work recently published by Aune shows that an

intake of 800 g of fruit and vegetables per day has cardiovascular benefits. The circle

is complete.

Data such as this cannot remain unheeded. It is time to give consumers – whether



healthy or otherwise – the keys to changing their eating habits."


Is it a worse possibility to do nutrition studies than observational epidemiology?
no.


In another paper which is a review one can read this table. Where are the pieces of evidence for 11 servings of grains?
Nowhere!


Food groups and recommended servings per day.

Food groupRecommended servings per day
Vegetables, all types including starchy vegetablesAd libitum, with a variety of colors represented
Fruits, all types2–4 servings (1 serving = 1 medium piece of 1/2 cup)
Whole grains (e.g., brown rice, quinoa, oats)6–11 servings (1 serving = 1/2 cup cooked or 1 slice whole grain bread)
Legumes (beans, lentils, peas, soy foods)2–3 servings (1 serving = 1/2 cup cooked)
Leafy green vegetables (e.g., broccoli, cabbage, lettuce)At least 2–3 servings (1 serving = 1 cup raw or 1/2 cup cooked)
Nuts (e.g., almonds, pecans, walnuts)1–2 ounces
Seeds (e.g., chia, flax, hemp seeds)1–3 tablespoons
Fortified plant milks (e.g., almond, soy, rice)Optional, 2–3 cups
Fresh herbs and spicesOptional, ad libitum

http://europepmc.org/articles/PMC5466942;jsessionid=561BF4246B96D7AAABDC06776BEEBDA0
In another irrational assessment, authors showed this figure. The culprit is FAT on the left which is completely false as all but dairy are foods without a big amount of fat... Those authors are fatphobic and it shows.

http://europepmc.org/articles/PMC5466942/bin/jgc-14-05-355-g001.jpg 

"8. Dietary fatty acids

Compared to other nutrient recommendations, the dietary fat acceptable macronutrient distribution range (AMDR) is wide, ranging from 20% to 35% of total calories for adults after 19 years of age.[96] This range is intended to provide enough fat calories as energy while decreasing risk of chronic disease. However, there are more specific guidelines when it comes to the different types of fatty acids, as although they may be isocaloric, they are not isometabolic and hence impart unique influences on health.
Polyunsaturated fatty acids—namely omega-3 and omega-6—are the only essential fats in the diet. Omega-3 fats are found in their shorter chain form as alpha linolenic acid (ALA) and are used as energy and also converted by the body to the longer chain eicosapentaenoic acid (EPA) and then docosahexaenoic acid (DHA).[104] ALA can be found in flaxseeds, hemp seeds, chia seeds, leafy green vegetables (both terrestrial and marine), soybeans and soy products, walnuts, and wheat germ, as well as in their respective oils. A direct plant source of EPA and DHA is microalgal oil, through which fish acquire them.[105][110] Plant sources are superior because they do not contain the contaminants that fish contain, including heavy metals, such as mercury, lead, and cadmium, industrial pollutants like dichlorodiphenyltrichloroethane, polychlorinated biphenyls, and dioxin, and possibly even radioactive isotopes.[111][114] The AI for ALA is 1.1 g per day for adult females and 1.6 g per day for men. Conversion of ALA to EPA and DHA is limited in humans.[115],[116] Serum and adipose levels of EPA and DHA have been found to be significantly lower in vegetarians and vegans when compared to omnivores, although there is no evidence of any adverse health or cognitive effects.[117],[118] Vegetarians, vegans, and those with reduced conversion ability, such as the elderly, may benefit from doubling the recommended dose of ALA (2.2 g for females and 3.2 g for males per day) and adding a microalgal supplement.[107],[119]
As omega-6 fats (linoleic acid), are available ubiquitously in the food supply in the seeds of most plants, they are not a nutrient of concern. In fact, Western diets tend to be excessive in omega-6 fats due to their prevalence in processed foods, which are also low in omega-3 fats. The resultant elevated omega-6/omega-3 ratio has been associated with inflammation and increased chronic disease risk.[120],[121] This adverse ratio can be attenuated by ensuring adequate omega-3 intake and minimizing the consumption of highly processed foods.
Mono-unsaturated fats are not essential, but impart either a neutral or slightly beneficial effect on serum cholesterol levels, depending on which nutrient they are replacing. When swapped for saturated or trans fats or refined carbohydrates, monounsaturated fats may lower low density lipoprotein cholesterol (LDL-C) and raise high density lipoprotein cholesterol (HDL-C) cholesterol.[33] These fatty acids are found in olives, avocados, macadamia nuts, hazelnuts, pecans, peanuts, and their respective oils, as well as in canola, sunflower, and safflower oils.
Saturated fats are not essential in the diet and can promote cardiovascular disease.[33],[122],[123] 
This statement is so wrong that it should be considered as a lie. After several meta-analysis and meticulous studies, after the discovering that Ancel Keys manipulated data, after the failure of the cholesterol hypothesis it is dangerous to repeat such statements from the sixties.

They are found primarily in animal products, but are available in some plant foods, mostly in tropical fats and oils, such as palm and coconut, and also in other high-fat foods, including avocados, olives, nuts, and seeds. The American Heart Association recommends limiting saturated fat to less than 5 to 6 percent of total calories (about 14 g total on a 2000 calorie per day diet).[124] While recent headlines may cast doubt on the adverse impact of saturated fat, the preponderance of the evidence supports its reduction.[123],[125] Underlying mechanisms, metabolic ward studies, and wider observational studies of the last century are still supportive of the reduction of saturated fat.[126][128]
Siri-Tarino and others will undoubtedly appreciate the "recent headlines". Be careful headlines and journalists could more rational and less brainwashed by the lipid-heart hypothesis.
Trans fatty acids (TFAs) are lab-made via hydrogenation and are found in processed, fried, and fast foods. Although they were originally developed to be a healthy alternative to butter and lard, TFAs were found to increase cardiovascular disease risk.[33] In November 2013, the United States Food and Drug Administration (FDA) issued a notice that TFAs were no longer considered safe; the FDA is now trying to eliminate artificially produced TFAs (small amounts are found naturally in some meat and dairy products) from the food supply. Note that a nutritional label can state a food product contains “0 g trans fats” even if it contains up to 0.5 g per serving. Thus, advise patients to focus on the ingredient list on food products and avoid anything with the words “hydrogenated” or “partially hydrogenated.”
Dietary cholesterol is a sterol found only in animal products. Although cholesterol is necessary for the production of hormones, vitamin D, and bile acids, the liver produces adequate quantities of cholesterol and exogenous intake is unnecessary. Dietary cholesterol's impact on plasma cholesterol is less significant than saturated fat's, and absorption may be highly individualized, but it nonetheless, may have a significant impact on some individuals and impact may only manifest when individual plasma lipid concentrations are low.[129][132] Saturated fat may potentiate dietary cholesterol absorption and endogenous synthesis.[133],[134]

This is completely wrong despite the restriction used in some sentences. Dietary cholesterol has nothing to do with atheroma.



Phytosterols, another class of fats, are plant-based sterols found in all plant foods (especially wheat germ, nuts, seeds, whole grains, legumes, and unrefined plant oils), which are similar to cholesterol. Phytosterols reduce cholesterol absorption in the gut, thereby optimizing lipid profiles. Together with viscous fibers, soy proteins, and almonds, phytosterols have been found to be as effective as statins in lowering LDL-C.[15],
Can you ignore the concerns about plant sterols?
1. Weingärtner O, Böhm M, Laufs U. Controversial role of plant sterol esters in the management of hypercholesterolaemia. Eur Heart J. 2009;30:404–409. doi:10.1093/eurheartj/ehn580[PMC free article][PubMed]
2. Schonfeld G. Plant sterols in atherosclerosis prevention. Am J Clin Nutr. 2010;92:3–4.doi:10.3945/ajcn.2010.29828[PubMed]
3. Salen G, Horak I, Rothkopf M, Cohen JL, Speck J, Tint GS, Shore V, Dayal B, Chen T, Shefer S. Lethal atherosclerosis associated with abnormal plasma and tissue sterol composition in sitosterolemia with xanthomatosis. J Lipid Res. 1985;26:1126–1133. [PubMed]
4. Payne MY. Too young to be having a heart attack. Lancet. 2001;358(uppl)):S64. doi:10.1016/S0140-6736(01)07076-3[PubMed]




Overall, some dietary fat is necessary to meet the essential fatty acid requirements. Whole food sources of fat (e.g., nuts, seeds, avocados) should be prioritized over processed fats (e.g., oils). Oils provide excess energy (more than 2000 calories per cup) with minimal nutrition including zero fiber.
While nearly a century of macronutrient-centric education has created widespread familiarity with these terms, it may also add a layer of complexity and confusion in chasing mythical macronutrient ratios that seem yet unresolved. Organizing food into isoenergetic macronutrient categories may create a false equivalency of non isometabolic food (e.g., refined sugar versus legumes). This false equivalency may contribute to apparent contradiction in dietary studies and create unnecessary complexity in patient messaging; for example, “choose low glycemic, complex carbohydrates” instead of simple messaging, “eat carrots.” “Eat towards the right side of the Food Triangle” is a simple food-centric instruction that naturally restricts specific deleterious nutrients (e.g., saturated/trans fatty acids, refined sugars, while increasing beneficial nutrients (e.g., dietary fiber, vitamins, minerals, phytonutrients)."
Interesting. But the main problem is ignored. It is the widespread use of sugar on every meal every plate and every day. And for obscure reasons you didn't deal with the cause...

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