How much fat can I have a day?

Depends on your eating plan. I eat low carb, so the majority of my calories come from fat, then the second most is protein and the last bit are carbs from veggies or other small sources. So if you're eating low carb, your fat needs to be high. Fats are good for you, especially if you're female. They help regulate hormones.

forgtmenot wrote: »

The truth is, however, that there is no direct connection between the amount of cholesterol you eat and the concentration of cholesterol in your blood. In most people, eating cholesterol has little or no effect on this amount. In about 30 percent of the population, eating cholesterol does in fact increase the concentration of cholesterol in the blood — but it increases the "good" cholesterol.

To put it in more scientific terms, eating cholesterol "results in a less atherogenic lipoprotein profile."

^this is the same thing I learned in Biology II in college. As a science major I've learned my fair share of biology, specifically human anatomy. Scientists did once believe that eating cholesterol=cholesterol in the blood, but have since found out that that is not accurate. So... Go ahead and eat some eggs.

Nobody argued that -- I think most people know now that dietary cholesterol != blood cholesterol. This discussion about sourcing the fat macro from saturated/unsaturated fats was born out of this exchange:

[...] but only good fats : salmon, nuts olive oil.

Pu_239 wrote: »
The fats you listed I don't think they're the healthiest.

There is nothing wrong with getting dietary fat from salmon, nuts, and olive oil. I wanted to make the point that these are perfectly healthy fats, and Pu_239 should not be recommending that people must replace the majority of their fish/nuts/olive oil with saturated fats.

Pu_239 wrote: »

I can't forsee any other way for a phospholipid to be synthesis. Due to the fact one of the tails is a saturated fatty acid chain. The other tail is not, hence half is saturated fats. It takes a lot of energy to break a double bonded carbon the types in unsaturated fats. To convert an unsaturated fat in to a saturated fat just doesn't seem realistic. Since Molecules takes the path of least resistances and go to the lower energy state. There might be some exceptions in certain situations but I don't see it being the norm.

Ah, I see where the confusion is coming from now! To be clear, this is NOT a personal vendetta against saturated fats -- my diary's open, so you can see that I have ~20g/day of unsalted butter during the workweek.

Dietary fat is mostly triglycerides, cholesterol, and phospholipids. We aren't really arguing cholesterol here (a totally different discussion, I think, and one we agree on based on what you've said previously), we're talking about triglycerides and phospholipids. The original discussion was sparked from the question/claim that cellular membranes are made of phospholipids, so we should eat more saturated fat than unsaturated fat to synthesize more cellular membranes.



The phospholipid bilayer is made of up phospholipids (duh), a mix of saturated and unsaturated (the kinked tails are unsaturated, straight ones are saturated, which I think you know already but I'll just restate for the benefit of lurkers).

This leads me to ask what, if any, is the difference in composition (TGs, phospholipids) between saturated and unsaturated fat? That lead me here, and to this handy chart:



Awesome, I think this can help answer my (our?) question! A line in that link says, "Thus, cells of all species have mechanisms to change the relative amounts of saturated fats and unsaturated fats in their cell membranes. The higher the cell's growth temperature, the less unsaturated material; the lower the temperature the more unsaturated material. This turns out to be essential for survival."

This makes sense. This is why your diet can be vegan (unsaturated fat sources like nuts and seeds) or keto (saturated fat sources like beef and butter), and you'll be fine either way, it'll just convert whatever it has a surplus of into whatever it has a dirth of. NEAT!

caveat: this doesn't get into the essential fatty acid discussion...

FunkyTobias wrote: »

I find it hilarious that many of the same people who trot out the "carbs are not essential" argument also love to recommend high intakes of saturated fat. I guess their low-carb gurus never told them that there are no essential saturated fats either.

Yup.

David Katz on that same thing (with links):

http://www.huffingtonpost.com/david-katz-md/study-saturated-fat-as-ba_b_5507184.html

A recent meta-analysis by an accomplished international team of researchers, published in a prestigious medical journal, shows that high intake of saturated fat is exactly as bad for health as a high intake of sugar and refined starch. The study also suggests there is something far worse.

The study, which pooled data from prior research and in the process aggregated findings for over 500,000 people, compared the rates of coronary artery disease -- the particular bad health outcome on which the researchers chose to focus for fairly obvious, epidemiologic reasons -- between those with the highest intake of saturated fat as a percent of calories, and the correspondingly lowest intake of refined starch and added sugar; to those with the highest intake of sugar and refined carbohydrate, and correspondingly lowest intake of saturated fat. The rate of cardiovascular disease was virtually identical in both groups.

This indicates that a high intake of saturated fat is as bad as a high intake of sugar, as well as vice versa.

OK, now that I presumably have your attention, I'll tell you my real agenda, which has nothing to do with saturated fat, or sugar, and everything to do with stupidity. Because, folks, when it comes to food, and food for thought alike, it is mostly stupidity that is killing us. Stupidity is worse for us than either sugar or saturated fat.

* * *

We do, in fact, know what dietary patterns are associated with optimal health outcomes. We know it based on vast, diverse, robust, and astonishingly consistent evidence. As evidence of the consistency of the evidence, I reached a particular set of conclusions based on my commissioned review of the literature with one set of analytical objectives. Dr. Frank Hu at Harvard and his colleagues reached a virtually identical set of conclusions based on an entirely independent review of the literature born of a different set of analytical objectives.

We are not clueless about the basic care and feeding of Homo sapiens. We really are not.

But eating well cannot be achieved by shifting from one scapegoat to the next; that merely invites new ways to eat badly. It can't be done one nutrient at a time. If ever there was a case of fixating on a tree while the forest burns down, modern trends in nutrition exemplify it.

* * *

No, saturated fat is NOT our nutritional nemesis, and never was. But neither is sugar, nor wheat, nor all grains. No one thing is THE thing wrong with our diets, and no one food, nutrient, or ingredient will be our salvation either. Wholesome foods, mostly plants, in sensible combinations could be -- assuming an 80 percent reduction in all chronic disease qualifies as salvation. It's about as close as we can come in the context of epidemiology, and pretty darn good.

What stands in the way is not our admittedly imperfect knowledge of nutrition, because frankly, we know enough. What stands in the way is hyperbolic headlines, fixed agendas, reactionism, religious zeal, profiteering, finding only what we're seeking, and failure to learn from the follies of history.

In other words, what is far more perilous to our health than saturated fat or sugar is the prevailing standard of stupidity in the food for thought we swallow routinely. If there is a war to be waged against anything ingestible, I humbly suggest it be that.

You are missing the point entirely.

However, if we want to go there, his actual recommendations are pretty much the conventional nutrition advice. He particularly likes the Med diet* (I get the sense this is not unrelated to taste preference), and recommends standard macros: less than 30% of calories from fat (less than 7% from saturated fat), 45-60% from carbs (but not generally highly processed carbs), fiber at least 25-35 grams, at least half (or more, ideally) of grains from whole grains, lots of fruits and veggies, 15-30% of calories from protein, 3-4 servings of beans and legumes per week, 3-4 servings of fish and shellfish per week (if one is not a vegetarian, of course), limit red meat, eat nuts and seeds 4-5 times per week.

About GI and GL he says: "[a]s with a hammer or saw, these tools are only as good as the person's ability to use them." He seems to like GL much better than GI, which is sensible, and likes GI basically as a way to pick among foods in a category without being rigid about it (i.e., he'd certainly prefer whole grains to more refined, but doesn't insist that one cut out white pasta).

*One problem with how everyone recommends the Med diet is that I think the genuine Med diet IS or WAS higher in fat than is typically recommended and while I understand the reasoning for reducing sat fat while being somewhat skeptical about some of that, I've never seen the reasoning for fat below 30% and carbs over 45%, and I haven't found Katz's reasoning for those broader numbers, although I have some stuff to read I haven't gotten to yet.