Sodium Nitrite vs Partially Hydrogenated Oils: which is worse?

What is Sodium Nitrite?

Sodium nitrite (NaNO2) is a salt and food additive used as a preservative, color fixative, and curing agent in processed meats. It gives cured meats (bacon, hot dogs, ham) their characteristic pink color and prevents the growth of Clostridium botulinum bacteria that cause botulism.

What is Partially Hydrogenated Oils?

Partially hydrogenated oils (PHOs) are vegetable oils that have been treated with hydrogen gas in the presence of a catalyst to make them semi-solid at room temperature. This process creates artificial trans fatty acids (trans fats) as a byproduct. They were developed in the early 20th century as a cheaper, longer-lasting alternative to lard and butter.

Documented risks

Sodium Nitrite: Sodium nitrite's primary health concern is the formation of nitrosamines. Under cooking heat or in the acidic environment of the stomach, nitrite can react with secondary amines (found in protein-rich foods) to form N-nitrosamines — a class of potent carcinogens. Several N-nitrosamines are classified as Group 1 or Group 2A carcinogens by IARC. The association between processed meat consumption and colorectal cancer is well established. IARC classified processed meat (including nitrite-cured meats like bacon, hot dogs, and ham) as a Group 1 human carcinogen in 2015, citing sufficient evidence from epidemiological studies. A comprehensive meta-analysis found that each 50g/day increase in processed meat consumption was associated with an 18% increase in colorectal cancer risk. Nitrite can also be converted to nitric oxide (NO) in the body, which at high doses can oxidize hemoglobin to methemoglobin — a condition called methemoglobinemia (or 'blue baby syndrome') that impairs oxygen transport. This is particularly dangerous for infants, which is why baby food with added nitrite is banned across the EU. However, many experts argue that the actual dietary cancer risk from nitrite in cured meats is difficult to separate from other components of processed meat (saturated fat, heme iron, cooking methods like smoking and charring) that also generate carcinogenic compounds. The paradox of nitrite regulation: the FDA requires it in some meat products for botulism prevention — making total elimination potentially more dangerous than restricted use. The focus of public health guidance is reducing consumption of processed meats, not eliminating nitrite entirely.

Partially Hydrogenated Oils: Artificial trans fats (from PHOs) have the most well-established cardiovascular harm of any food ingredient ever banned. Multiple large meta-analyses have confirmed that trans fat consumption increases LDL ('bad') cholesterol, decreases HDL ('good') cholesterol, increases inflammatory markers, and significantly raises cardiovascular disease risk. The Harvard Nurses' Health Study and other landmark prospective studies in the 1990s identified trans fat as uniquely harmful — worse than saturated fat in its cardiovascular effects. A 2006 NEJM meta-analysis by Mozaffarian et al. estimated that eliminating artificial trans fats from the US diet could prevent 72,000 to 228,000 heart attacks per year and 30,000 to 100,000 coronary heart disease deaths annually. The WHO estimates that industrially produced trans fats cause over 500,000 cardiovascular deaths per year globally. The FDA revoked PHOs' GRAS status in 2015 based on this evidence, with compliance by 2018. Denmark banned artificial trans fats in 2003, the first country to do so, and observed a dramatic reduction in cardiovascular mortality in subsequent years.