The Hateful Eight Seed Oils — What They Are and Why to Avoid Them

The term 'hateful eight' refers to eight industrial seed oils that entered the American food supply during the twentieth century and now appear in the majority of packaged foods, restaurant meals, and supermarket cooking products. These oils did not exist before 1900. They were extracted from seeds using chemical solvents, deodorised at high temperatures, and marketed as healthier alternatives to the animal fats that people had cooked with for thousands of years.

The case against them centres on omega-6 linoleic acid. All eight oils are high in it. Linoleic acid accumulates in human body fat over years, and the linoleic acid content of American adipose tissue has doubled since 1959, tracking almost exactly with increased seed oil consumption. Whether that accumulation is harmful is still debated in formal nutritional science. In the MAHA community, the debate is largely settled.

The Eight Oils — One by One

1. Canola Oil

Derived from rapeseed, a plant not historically used for food. The name 'canola' is a marketing term coined in the 1970s — 'Canadian oil, low acid.' It is the most widely used seed oil in North America and appears in more packaged foods than any other on this list. The low-erucic acid variety was bred to remove rapeseed's original toxin, but the resulting oil is still chemically extracted using hexane solvent and deodorised above 200°C.

2. Soybean Oil

The single most consumed oil in the United States by volume, primarily because it is used in commercial food manufacturing at scale. Most American soybean oil comes from genetically modified soybeans. It is approximately 54% linoleic acid and contains phytoestrogens. A 2020 study at UC Riverside linked soybean oil consumption in mice to neurological changes affecting genes associated with oxytocin signalling.

3. Sunflower Oil

Approximately 68% linoleic acid — among the highest on this list. Standard sunflower oil oxidises rapidly at cooking temperatures and produces aldehydes when heated above its smoke point. These oxidation products have been associated with inflammation and cellular damage. High-oleic sunflower oil variants are more stable, but still industrially processed.

4. Safflower Oil

At 75% linoleic acid, safflower oil is one of the most omega-6-concentrated cooking fats available. It is chemically unstable when heated and is found in salad dressings, mayonnaise, and margarine. It is often marketed as heart-healthy based on older research that is now substantially contested.

5. Corn Oil

A byproduct of corn wet-milling — it would not exist without the industrial infrastructure built around high-fructose corn syrup. Approximately 57% linoleic acid. Corn oil was heavily promoted for decades as cholesterol-lowering. A re-analysis of the original Sydney Diet Heart Study found that replacing saturated fat with corn oil increased all-cause mortality by 62%, a finding that received little mainstream attention at the time.

6. Cottonseed Oil

The original industrial seed oil, used in Crisco shortening when it launched in 1911. Cottonseed is technically a byproduct of the cotton industry — the oil required chemical treatment to remove gossypol, a natural toxin, before it could be consumed. It is approximately 54% linoleic acid and was historically associated with pesticide contamination from cotton agriculture.

7. Grapeseed Oil

Marketed as premium and natural but industrially extracted from the seeds discarded during winemaking. Approximately 70% linoleic acid. Most commercial grapeseed oil uses hexane solvent extraction. Its high smoke point reflects the deodorisation process rather than chemical stability at temperature.

8. Rice Bran Oil

Extracted from the outer layer of rice grains. Popular in Asian food manufacturing and increasingly in Western health food markets. Approximately 37% linoleic acid — lower than most on this list, but still industrially processed. Its smoke point (around 450°F) is often cited as an advantage, but the deodorisation process that produces a high smoke point does not confer chemical stability.

What to Use Instead

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Part of: Seed Oils 101 — What They Are and How to Avoid Them