Foods and Substances to Avoid for Maximum Health and Longevity

Sub-article of Nutrition — Wheel of Health. See also: Seed Oils, Alcohol, The Biggest Levers.

Twelve foods and substances, ranked from the one that does the most harm to the most people down to the ones worth attention only once the top of the list is gone. The first four are trans fats and heated oils, sugar and sugary drinks, alcohol, and white flour. Cut those and most of the damage food does to a modern body has already stopped.

1. Why Removal Comes First

The most damaging foods share one mechanism: they drive chronic inflammation, insulin resistance, oxidative stress and hormonal disruption. Take them away and the body’s own repair has room to work. Add supplements while they remain and the repair is spent undoing each day’s damage, which is why cutting the first three items on this list does more than adding ten supplements. Two things decide each item’s place: how much harm it does per mouthful, and how much of it an ordinary diet contains.

2. The Ranking

1. Trans fats and heated industrial oils

Partially hydrogenated oils damage the lining of the arteries and have no safe intake. The World Health Organization attributes more than 278,000 deaths a year to industrially produced trans fat, carried in margarine, shortening, vanaspati, fried food, biscuits and pies (WHO). Industrial seed oils, soybean, corn, canola, sunflower and safflower, do their damage in the pan. At frying heat they oxidize into aldehydes, lipid peroxides and polymers that are toxic to cells, and the damage grows with the temperature and with every reuse of the oil. They also tilt the diet far toward omega-6 fats and away from omega-3.

Commercially fried food stacks every one of these harms: oxidized fat, acrylamide from starch cooked at high heat, a flour coating that soaks up still more oil, and advanced glycation end-products. Crisps belong here too, sliced thin so the oil has the most surface to cling to.

The fault lies in the industrial process and the frying pan. Cold-pressed flax, hemp, pumpkin and black seed oils, kept in dark glass and taken raw, stay on the table (Seed Oils).

Instead: cook with ghee, tallow or coconut oil, and extra-virgin olive oil at moderate heat. Fried food from a restaurant fryer, never.

2. Sugar and sugary drinks

Refined sugar and high-fructose corn syrup drive fat into the liver, insulin resistance and glycation damage. The liver metabolizes almost all fructose and turns the excess into fat; Robert Lustig’s comparison with alcohol names that shared route, not an equal harm. Sugar is at its worst drunk. Soft drinks, juice and sweetened tea or coffee deliver it without the fibre and chewing that slow its arrival, and sugar-sweetened drinks were linked to 2.2 million new cases of type 2 diabetes and 1.2 million of cardiovascular disease worldwide in 2020, about one new diabetes case in ten (Lara-Castor et al., Nature Medicine, 2025).

Instead: water, and tea or coffee without sugar. Whole fruit in place of juice.

3. Alcohol

Ethanol damages the liver and the brain, causes cancer from the first drink, and breaks up sleep even at moderate doses. The protection once claimed for moderate drinking disappears when former drinkers and the already ill are removed from the non-drinking comparison group. The World Health Organization attributes 2.6 million deaths a year to alcohol (WHO).

Target: zero. The full reading is at Alcohol.

4. White flour and refined carbohydrates

White flour, white rice, and most bread and pasta act on blood sugar almost as sugar does: a fast glucose spike, a surge of insulin, inflammation downstream. Milling strips the grain of its bran and germ, and with them the fibre, minerals and oils that slowed its digestion. Outside the countries where packaged food dominates, white flour is the main industrial ingredient on the plate: the bakery loaf at every meal, the pastry, the semolina, eaten three times a day.

Instead: vegetables and intact whole grains, in the amounts your digestion tolerates. Bread at one meal, not three.

5. Ultra-processed food

Ultra-processed products bundle the four items above with emulsifiers, flavourings and textures engineered to be eaten past the point of fullness. The harm is now causal. At the US National Institutes of Health, twenty adults offered ultra-processed meals ate about 500 more calories a day than when offered minimally processed meals matched for nutrients (Hall et al., Cell Metabolism, 2019). In a British crossover trial published in 2025, fifty-five adults ate two diets that both met national guidelines; over eight weeks the minimally processed one produced twice the weight loss, 2.06% against 1.05%, all of it fat, and cravings roughly halved (Dicken et al., Nature Medicine). How much of a diet these products supply depends on the country: 58% of adult calories in the United States and 57% in Britain, against 30% in Mexico, 22% in Brazil and 18% in Italy (national survey figures compiled by the BMJ).

Instead: buy ingredients, not products. A label listing things you would never keep in a kitchen marks the product.

6. Processed meat

Ham, bacon, sausages, salami and other cured, smoked or nitrate-preserved meats are classed by the World Health Organization’s cancer agency as carcinogenic to humans; each 50 g eaten daily raises the risk of colorectal cancer by about 18% (IARC, 2015). They are tied to heart disease as well.

Instead: fresh fish, eggs, or fresh pasture-raised meat cooked gently.

7. Artificial sweeteners

Sucralose, aspartame and their kind disturb the microbiome, particularly by reducing bifidobacteria, and may interfere with insulin signalling through the cephalic phase response, a sweet taste with no calories to follow. The World Health Organization advised against non-sugar sweeteners for weight control in 2023, finding no long-term benefit for body fat in adults or children (WHO). A daily serving of sucralose-sweetened whey protein costs little against the protein it delivers.

Instead: stevia, monk fruit, or nothing sweet at all.

8. Plastic in contact with food

Bisphenol A (BPA) and phthalates are estrogenic compounds that leach from plastic into food, most of all when it is heated. In 2023 the European Food Safety Authority cut its tolerable daily intake for BPA 20,000-fold, to 0.2 nanograms per kilogram of body weight, and the European Union’s ban on BPA in food-contact materials has applied to most articles since 20 July 2026 (Regulation (EU) 2024/3190).

Instead: glass or stainless steel. Never heat food in plastic.

9. Charred and burnt food

Grilling, barbecuing and deep frying generate heterocyclic amines and advanced glycation end-products, both damaging to tissue.

Instead: steaming, stewing, and slow cooking at low heat.

10. Pesticide residues

The most heavily sprayed crops, the “Dirty Dozen”, carry residues that disrupt hormones at low doses over years.

Instead: organic for the most sprayed crops, and careful washing or peeling for the rest.

11. Factory-farmed meat and dairy

Animals raised on grain in confinement carry antibiotic residues, synthetic hormones and a fatty-acid profile that feeds inflammation.

Instead: pasture-raised, grass-fed or wild-caught, as the baseline standard.

12. Untreated tap water

Chlorine, fluoride, pharmaceutical residues and heavy metals reach the body through the water it drinks every day. Reverse osmosis followed by distillation is the standard, with minerals chosen and added by hand rather than put back by a remineralization cartridge (Hydration).

3. How to Use the Ranking

Start at number one and work down. The common failure runs the other way: people buy organic produce and filter their water while still frying in seed oil and drinking soda every day, and the effort at the bottom of the list is lost to the damage at the top. The first four items are cut entirely. Ultra-processed food and processed meat become rare exceptions. Items seven to twelve matter, and their signal emerges once the top of the list is gone.

Two habits sit beside the list. Caffeine taken late in the day disturbs the cortisol rhythm and the architecture of sleep, so it belongs to the morning. And constant eating keeps insulin high and holds off autophagy whatever the quality of the food, so meals are spaced and the day’s eating window is closed early (The Fasting Principle).

4. What This List Leaves Out

Tobacco is no food, and it heads the biggest levers for health, where the target is zero nicotine in any form. What to eat, protein first and good fats second, belongs to Nutrition; what to add as supplements belongs to Supplementation.