Partially Hydrogenated Oils vs Sodium Nitrate: which is worse?

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.

What is Sodium Nitrate?

Sodium nitrate (NaNO3) is a naturally occurring salt found in soil and some plants, and also synthetically produced for use as a food preservative and curing agent. It is converted to sodium nitrite by bacterial action in foods or in the body, where it exerts its preservative and curing effects. Sometimes called 'Chile saltpeter' after its natural South American ore source.

Documented risks

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.

Sodium Nitrate: Sodium nitrate shares the same health concerns as sodium nitrite: conversion to nitrosamines is the primary mechanism of concern. Sodium nitrate is converted to nitrite by bacterial reduction in foods and by nitrate-reducing bacteria in saliva before reaching the stomach. The subsequent conversion of nitrite to nitrosamines carries the same carcinogenicity concerns described for sodium nitrite. IARC's 2015 classification of processed meat as Group 1 human carcinogen applies to all nitrite/nitrate-cured processed meats. EFSA's 2017 re-evaluation established acceptable daily intakes (ADIs) for nitrate (3.7 mg/kg body weight/day) and nitrite (0.07 mg/kg body weight/day) based on risk assessment. A notable paradox in nitrate nutrition: dietary nitrate from vegetables (particularly leafy greens like spinach, arugula, and lettuce, and root vegetables like beets) is associated with cardioprotective effects through the nitrate-nitrite-NO pathway, where nitric oxide from dietary nitrate improves vascular function and reduces blood pressure. This beneficial effect of vegetable nitrate contrasts with the potential harm from processed meat nitrate/nitrite, suggesting that the food matrix and associated compounds (antioxidants in vegetables vs. amines in meat protein) significantly influence whether nitrite produces beneficial or harmful effects. Infant exposure to high nitrate levels — particularly from well water — can cause methemoglobinemia ('blue baby syndrome'). The EU and WHO set strict nitrate limits for infant water and food for this reason.