Does sunflower oil reduce LDL ("bad") cholesterol more than olive oil?

Question

The Sun writes: FLOWER POWER Sunflower oil is ‘BETTER’ for your heart than olive oil – and it’s much cheaper

FOR years, we've been told that olive oil is the healthiest oil to cook with and dress our food in.

But a new study suggests that seed oils might be better for reducing cholesterol than the more expensive Mediterranean variety.

[...] they compared the effect of 13 oils and fats: safflower oil, sunflower oil, rapeseed oil, flaxseed oil, olive oil, hempseed oil, corn oil, coconut oil, palm oil, soybean oil, butter, beef fat, and lard.

The "best performers", according to the study, were sunflower, safflower, rapeseed and flaxseed oil.

Is the claim that using sunflower oil better than using olive oil at keeping LDL cholesterol low true?

Answer 1

According to the mentioned study review, when used instead of butter, sunflower oil was associated with greater reduction of total and LDL cholesterl than olive oil. No other blood parameters or health outcomes were compared.

From the original paper (they included randomized trials lasting >3 weeks): Effects of oils and solid fats on blood lipids: a systematic review and network meta-analysis (Journal of Lipid Research, 2018):

Each 10% of dietary energy from butter replaced with an equivalent amount of safflower, sunflower, rapeseed, flaxseed, corn, olive, soybean, palm, and coconut oil, and beef fat was more effective in reducing LDL-C (−0.42 to −0.23 mmol/l)... Moreover, sunflower oil was more effective in reducing LDL-C than olive and palm oil (−0.10 to −0.09 mmol/l).

and

Despite the limitations of the NMA approach and the overall low quality of evidence judgements, the NMA findings are in line with existing evidence on the metabolic effects of fat, and support current recommendations to replace high saturated-fat food with unsaturated oils.

I haven't found a single study that would compare the preventative effect of sunflower and olive oil on actual health outcomes: cardiovascular or other disease. There is some weak evidence that the olive oil intake is associated with a lower risk of cardiovascular disease (covered on Medical SE).

I don't want to make any firm conclusions from a study for which even their authors say that is based on weak evidence.

Answer 2

I don't think one can really answer, because what is good or bad for anyone's particular biology is largely variable. We can determine that, yes, generally, this kind of oil is pretty good or bad, comparatively, but when faced with relatively healthy oils, you'd be hard-pressed to say "Oil A is 15% healthier than Oil B".

We know that monosaturated fats are some of the healthiest oils there are for human consumption.

Also vital and needed for good health are polyunsaturated fats, which include Omega 3 and Omega 6 fats.

Saturated fats are considered less healthy, but even that is being re-evaluated in light of things that were done to avoid saturated fats (use of trans fat subsitutes, for example).

And trans fats have been found, after much use, to be pretty much evil for the body. Oops.

What are fats? The real skinny on healthy fats and harmful fats

The other answer referenced a specific study where it seemed that sunflower oil was better for cardiac health results. Obviously, more results are needed before anyone outside of a marketing department can declare anything definitive.

What is interesting is that olive oil is higher in monosaturated fats, but also higher in saturated fats, with sunflower oil having more polyunsaturated fats. of, is there an ideal ration of one to the other? Depending on the opinion of which factor is most important (let alone how a composite evaluation is determined), the question of "better" seems to be unresolved, at this time.

{PDF} Oils Comparison Chart

What is still at issue is that we know that "bad fats" are to be avoided, and "good fats" are a better choice, but here we have have, open, the question of whether one good fat is more helpful than another, and the jury still seems to be out on that.

If monosaturated is better, than olive oil would be the choice. If the amount of saturated fat is more vital, then sunflower oil. If polyunsaturated fats, especially Omega Threes, from any source, help reduce cardiac risk, then sunflower oil. If vegetable sources for Omega Three fats don't work the same as fish-based oils, then that advantage is not present, and we just don't know yet. You can't find any recommendations out there that give specific advice of more than one "good" fat vs another.

The potentially helpful types of dietary fat are primarily unsaturated fats:

Monounsaturated fatty acids. This type of fat is found in a variety of foods and oils. Studies show that eating foods rich in monounsaturated fatty acids instead of saturated fats improves blood cholesterol levels, which can decrease your risk of heart disease and may also help decrease the risk of type 2 diabetes.

Polyunsaturated fatty acids. This type of fat is found mostly in plant-based foods and oils. Evidence shows that eating foods rich in polyunsaturated fatty acids instead of saturated fats improves blood cholesterol levels, which can decrease your risk of heart disease and may also help decrease the risk of type 2 diabetes.

Omega-3 fatty acids. One type of polyunsaturated fat is made up of mainly omega-3 fatty acids and may be especially beneficial for heart health. Omega-3, found in some types of fatty fish, appears to decrease the risk of coronary artery disease. There are plant sources of omega-3 fatty acids. However, it hasn't yet been determined whether replacements for fish oil — plant-based or krill — have the same health effects as omega-3 fatty acid from fish.

...... Avoid trans fat. Limit saturated fat to less than 10 percent of calories a day. Replace saturated fat with healthier monounsaturated and polyunsaturated fats.

Mayo Clinic - Dietary fats: Know which types to choose