More likely than something nefarious, I think it's more likely that both kinds of fat have differing adverse health effects. Saturated fats, as this paper sugge

More likely than something nefarious, I think it's more likely that both kinds of fat have differing adverse health effects. Saturated fats, as this paper suggests, increase LDL, which is bad for heart health. Polyunsaturated fats, especially when used as cooking oils, introduce free radicals that may cause a host of modern health issues, such as Alzheimer's, type 2 diabetes, and general aging [0][1][2]. The nature of agriculture has changed so much in the past 100 years that it's clear we don't know most of the consequences. Studies like this one correlate saturated fat to adverse health effects, but as far as I can tell they don't control for the quality of saturated fat used, lumping them all into the same statistical category. However, there is a substantive difference on health effects, including cholesterol levels, from grass-fed vs grain-fed meat [3], as well as other animal products like eggs and butter. Even worse is the inclusion of plant derived saturated fats like palm oil, which besides raising LDL [4], is a third-world environmental disaster. That being said, my recommendation is to avoid fried things as much as possible, especially when you don't know what it was fried in and how long that oil stayed hot. Buy grass-fed beef, milk, butter, etc at the store. Replace vegetable oil with olive oil and avocado oil. I could be wrong about this, but it aligns with the heuristic of eating as our ancestors did before the rise of industrial agriculture, and it tastes better. [0] https://www.semanticscholar.org/paper/Vegetable-Oil%3A-The-Real-Culprit-behind-Alzheimer%E2%80%99s-Yamashima/5c01a2d0ff93008de7e3f28e5b610d1752ffbac7 https://www.semanticscholar.org/paper/Vegetable-Oil%3A-The-R... [1] https://academic.oup.com/advances/article/11/6/1489/5867525?login=true https://academic.oup.com/advances/article/11/6/1489/5867525?... [2] https://www.tandfonline.com/doi/full/10.3109/10715762.2010.498478 https://www.tandfonline.com/doi/full/10.3109/10715762.2010.4... [3] https://nutritionj.biomedcentral.com/articles/10.1186/1475-2891-9-10?fbclid=IwAR01MjgGcX_tdkgN1gexqJzFQD4WxJ8LST8UDvq_Th4PxDQ164FdhtBwOh4 https://nutritionj.biomedcentral.com/articles/10.1186/1475-2... [4] https://academic.oup.com/jn/article/145/7/1549/4616780?login=true https://academic.oup.com/jn/article/145/7/1549/4616780?login...