I would be immensely skeptical of this unless he was talking about something much more narrow, like how there's a fraction of people who have really unfortunate genetics and can only improve their blood lipids with medication.
We have mountains of data showing that diet can massively improve lipids, and the combination of diet and exercise are our largest levers for reducing the risk of heart disease for most people. (There are always some fraction of people who can do everything right but have outlier genetics that require medication anyway, just as some people have outlier genetics and can smoke a pack a day their whole lives and reach their 90s.)
I'd check out the Barbell Medicine podcast for anything related to the intersection of lifestyle and health. They're extremely evidence based with a preference for measurable improvements in outcomes over hypothetical mechanisms.
Relevant to this thread are their episodes on testing and screening, hypertension / high blood pressure, cholesterol, fiber, and the new PREVENT heart disease risk calculator.
I'd also check out the episodes on diabetes, Alzheimer's, fatty liver disease, and health priorities.
I am one of those unfortunate genetic people, sadly, and have had high cholesterol numbers since my early 20s. Most of my older grandparents passed from heart disease. Now in my 40s, have a decent diet, and my numbers are < 100 for LDL. Current (and previous) PCPs have indicated to me that diet will have little effect for me, and that I will likely be on statins for most of my life. Experiments with stopping the statins have shot my LDL numbers through the roof.
The good news is that it's a pretty low dose with decently high effect.
I'm familiar with the genetically high cholesterol thing and when you look at that you see parents/grandparents having heart attacks in their 40's. nothing like any of that in my family.
anyway yes im on the statins and probably need to boost my dose a little more to be below 200.
They are unlikely to get lipid levels down low enough to reach soft plaque regression levels. You need to get sustained levels below 50 to 70 depending on genetics, Lp(a), etc.
If you've lived a healthy life in general and don't have genetically bad Lp(a) this advice is probably enough for you staying that way. If you've spent a significant portion of it with bad lipids for whatever reason, you almost certainly need to go on a combo therapy to get to regression levels.
These effects were first demonstrated in 1953. And has been confirmed over and over again since.
So don't discount the value of diet and exercise just because losing weight didn't fix your cholesterol.
still doesnt explain what my cardiologist was talking about, though. he's not the first dr. to tell me that "diet isn't really going to help you much". one dr. said, "if you went totally vegan, maybe it would have a slight effect". so no I didnt go totally vegan.
i think the idea is diet/exercise can make a 20 point dent in your total cholesterol but in practice, not much more than that, if you have total cholesterol over 250 kind of thing.
i don't know how to source that but I recall a few 20 points lower diets making the news over the years
not for me. My cholesterol was hovering in the high 200's, then finally hit 300 and I completely freaked out, radically changed my diet, and lost 22 pounds (from 180 to 158).
What did my high cholesterol do ? It did absolutely nothing. ticked down to like, 280.
So I'm on the statins. my total cholesterol went from high 200's to about 150 in a month and was impacting my liver function. so we reduced the statins to a very low dose (5mg three times a week, crazy low). My total cholesterol hovers around 200 now. My cardiologist tells me that the conventional wisdom of "diet and exercise" is almost entirely disproven to have any meaningful effect on lipids these days (though i havent researched deeply).