The current science does suggest eating too much fat is still bad.
EX: "The American Heart Association’s Nutrition Committee strongly advises these fat guidelines for healthy Americans over age 2:
•Eating between 25 and 35 percent of your total daily calories as fats from foods like fish, nuts, and vegetable oils."
Note both the lower and upper bound. Eating say 75% of your daily calories as fat is generally a bad idea for most people. But so is limiting yourself to 1%.
PS: This is one of those cases where oversimplification can be harmful. But, while looking at people with extremely high fat diets demonstrated a problem the translation from limit to eliminate is what most people heard.
According to that page you need to lower saturated fat to 5%-6% of calories. I'm suggesting that current science does not support the connection between saturated fat and heart disease. Nor does current science support their recommendation to cut salt. The AHA recommendations have been a dietary disaster for 30 years because they suggest that low fat food can be eaten without consequence, which has led to a massive uptake in the consumption of sugar and processed carbohydrates. And it was largely based on bad science.
> According to that page you need to lower saturated fat to 5%-6% of calories. I'm suggesting that current science does not support the connection between saturated fat and heart disease.
Studies, including recent ones, show that replacing saturated fat with polyunsaturated fat reduces cardiovascular disease risk (IIRC, in both sexes, but moreso in men than women.) Mostly, what's changed is that we now also have evidence that replacing saturated fat with trans fat or carbohydrates is, at best, no better than just staying with saturated fat.
There is probably no harm replacing saturated fat with polyunsaturated fat, but that's not what happened based on decades of AHA and govt. recommendations. What happened was that people replaced saturated fat with simple carbohydrates and trans fats, got fat, and had heart attacks. Take a look the heart safe foods the AHA currently approves. Bagels, rice, tortillas, orange juice, potatoes, cheerios. It is a recipe for obesity and illness.
You can't just pigeonhole fats into three categories and be done.
Butyric acid and stearic acid are both saturated fatty acids, but they serve very different roles in the diet. Similarly, ALA and LA are both essential unsaturated fatty acids, but they compete for the same desaturating and lengthening enzymes in the body. So if you eat sufficient quantities of those fatty acids in the wrong ratio, you can still see symptoms of dietary deficiency. And different people produce different quantities of those enzymes or different variations with greater or lesser effectiveness.
The AHA made insufficiently informed recommendations, and the nonscientific population followed them, often by replacing animal-based fats with vegetable-based fats with vastly different fatty acid ratios.
These were sometimes chemically treated to turn them into trans-fats, which in a key-keyhole model of body chemistry is like bending a kink into the key to your front door, then jamming it into the lock with a hammer and forcing it with vise-grips every time you wanted into your house. The trans fats resembled saturated fats enough to be used in the same way, but that kink in the key would cause persistent damage.
And foods manufacturers also replaced fats with sugars and sodium salts, which caused different problems.
Different foods have different fat profiles, just as they have different protein profiles. Eggs and milk have amino acid ratios that very closely match what humans need, whereas beans and rice are insufficient in isolation, but complete in combination. Similarly, beef suet, pork lard, olive oil, coconut oil, and soybean oil have different fat profiles.
We still don't know what the "best fat" food is, like we know that poultry eggs are very nearly the "best protein" food. And "fat quality" might not even be as homogenous between individuals as it is for the amino acids.
Any recommendations at this time are almost certainly unfounded or unsupported by rigorous and repeatable research. You really have to do your own homework on this one, and avoid making any conclusions based on insufficient evidence.
> There is probably no harm replacing saturated fat with polyunsaturated fat, but that's not what happened based on decades of AHA and govt. recommendations.
One of the leading hypotheses is that omega-6 fat - which is a subcategory of polyunsaturated - is very very bad for you. So there is absolutely potential for harm in replacing saturated fat with polyunsaturated fat.
EX: "The American Heart Association’s Nutrition Committee strongly advises these fat guidelines for healthy Americans over age 2: •Eating between 25 and 35 percent of your total daily calories as fats from foods like fish, nuts, and vegetable oils."
http://www.heart.org/HEARTORG/Conditions/Cholesterol/Prevent...
Note both the lower and upper bound. Eating say 75% of your daily calories as fat is generally a bad idea for most people. But so is limiting yourself to 1%.
PS: This is one of those cases where oversimplification can be harmful. But, while looking at people with extremely high fat diets demonstrated a problem the translation from limit to eliminate is what most people heard.