5 Harmful Foods To Avoid For Better Health & Weight Loss

Forbes

17-06-2025

When people decide it's time to eat healthier to lose weight or manage a health condition, they ask the same question: What should I eat? Answers typically come in the form of which diet to follow: keto, paleo, plant-based, Mediterranean or something else. But here's a better question and one that may lead to bigger, longer-lasting change: What harmful foods should I not eat?
We've lost sight of a deceptively simple truth. Most health improvements from dietary change don't come from adding so-called superfoods. They come from removing the foods that are actively hurting our health.
There may be individual reasons to follow a specific diet — food sensitivities, religious or cultural preferences or a physician's guidance. But for most, focusing on what not to eat may be the most impactful and sustainable diet of all.
The modern American diet is dominated by ultra-processed, calorie-dense nutrient-poor foods. More than 60% of the average American's calories come from ultra-processed products. Think packaged snacks, sugary drinks, frozen meals, fast food and refined carbohydrates.
These foods are actively harmful to health. Study after study links diets high in ultra-processed foods to obesity, heart disease, type 2 diabetes, cancer, and early death. In one randomized trial, just two weeks on an ultra-processed diet led to significant weight gain and increases in hunger hormones — even when calories and macronutrients (e.g. proteins, carbohydrates and fats) were matched.
Ultra-processed foods don't just make us sick, they're designed to override satiety signals, encouraging us to eat way more than we need.
People often begin a diet by trying to add in healthier foods: a protein shake, oatmeal with blueberries or a salad at lunch. That's great — unless it's followed by a soda and a bag of chips later.
Here's what works better: subtraction first.
Cutting out refined sugar, white flour, ultra-processed snacks and heavily refined seed oils creates space for healthier choices to naturally take their place. People often report feeling better, craving less and even losing weight without counting calories. Just by cutting out the junk food.
Think of it as nutritional minimalism: instead of obsessing over what to eat, ask what you can do without. This gives you flexibility. You can eat Mediterranean on Monday, Asian on Tuesday and plant-based on Wednesday. As long as the foods are whole and minimally processed, you're moving in the right direction.
Yes, calories matter. But where they come from matters more.
Two-hundred calories from salmon and broccoli is not the same as 200 calories from soda and cookies. The former fuels satiety, muscle repair and leads to stable blood sugar levels. The latter triggers glucose spikes, inflammation and rebound hunger.
The real issue isn't just overeating — it's over-consuming 'bad' calories. When you remove the foods that spike insulin, disrupt hormones and hijack appetite regulation, you naturally eat fewer total calories because your body self-regulates more effectively.
No matter the diet philosophy, there's surprising consensus among experts about what to avoid. Here are the top offenders:
Removing these — even partially — can improve energy, sleep, mood and hunger. Unlike restrictive diets, this lets you eat in any style that works for you — as long as you're cutting out the worst offenders.
Most diets fail not because people don't know what to eat, but because they're too complicated or rigid. A subtraction-first approach is simpler and more sustainable.
You don't have to adopt a 'perfect' diet overnight. Start with a single rule: no sugary drinks. Or avoid any product with more than five ingredients. These changes add up —gradually shifting habits often without requiring calorie tracking, apps or special meal plans.
This is also empowering. You're not relying on a meal delivery service or overpriced powders. You're simply removing low value and harmful foods.
There's a hidden psychological advantage too. When you focus on what not to eat, you reduce decision fatigue. Saying 'I don't drink soda' or 'I don't eat fast food' provides a mental shortcut. These are called identity-based habits — and research shows they're more durable than external rules, according to Atomic Habits author James Clear.
Yet taken to an extreme, this mindset can be problematic. It's not about cutting everything. It's about avoiding the foods most linked to fatigue, cravings and disease—not creating anxieties.
Importantly, it's not about perfection. A diet that's 90% clean is dramatically better than one that's 50%. Even halving your (or your kids') intake of ultra-processed food can yield meaningful results.
This 'cut the junk' strategy is increasingly backed by science. A 2024 BMJ study linked high ultra-processed food intake to higher risk of death from all causes.
Yet many diet plans still push complex and unsustainable approaches: 'Eat these 12 superfoods" or 'Only eat high-fat, high-protein, low carbohydrate foods.'
Sometimes the best advice is the simples: Eat real food; cut out the harmful foods; and let your body do the rest.