It seems like there are so many rules about what you can and can't or should and shouldn't eat.
As a general rule, food — real food, with as little processing or packaging as possible — is not bad for you. You can eat too much of many foods, especially foods that aren't vegetables, and most of us could improve our diets by eating more plant-based foods.
Here's what the science actually says about ingredients like salt, caffeine, and fat — and why you shouldn't worry about eating them, as long as it's in moderation.
Let's get straight to the good stuff — cheese can be part of a healthy diet.
Sure, cheese is often packed with saturated fat. It can be full of sodium too, and shouldn't make up the majority of your plate. But that doesn't mean you shouldn't eat one of the most delightful foods on the planet.
Cheese is nutrient-packed. It's also a good source of protein, calcium, vitamin B12, and healthy fatty acids that may lower diabetes risk. As a fermented food, it may help boost levels of good gut bacteria that are essential for health. Studies also indicate that cheese intake seems to be associated with a lower risk for heart disease and it may even lower levels of bad cholesterol, though more research is needed.
Eggs are excellent sources of protein and won't raise your cholesterol.
Eggs are fantastic sources of protein and they are full of other nutrients, including choline, a nutrient that's essential for brain development.
But eggs are also full of cholesterol, which for many years led researchers to encourage people to limit egg intake. Fortunately, that dietary recommendation has changed.
It turns out that for the vast majority of people, dietary cholesterol (from foods you eat) doesn't really have much of an effect on blood cholesterol.
Coffee — and caffeine in general — may provide significant health benefits and reduce cancer and liver disease risk.
You'll often hear people say that they're trying to limit themselves to one cup of coffee a day or to cut it out entirely.
But when you look at the health benefits associated with coffee consumption, you might wonder why. A significant body of research shows that drinking coffee is associated with a longer life. People who drink more coffee tend to have lower risk for heart disease, various cancers, liver conditions, and degenerative brain diseases.
It's possible to overdo it with caffeine, as too much at once can trigger anxiety or even be deadly. People usually need to consume it in a concentrated form to get that much into their bodies. But caffeine itself, even from non-coffee sources, is also associated with good health.
High-fat foods have long been demonized, but there's more and more recognition that they are essential.
More and more research shows that eating fat — the nutrient — doesn't necessarily cause body fat to increase.
We need fat to survive, especially healthy fats like those found in eggs, olive oil, and avocados. High-fat diets are not necessarily associated with heart disease, according to large reviews of research. And eating enough fat can help fuel activity and keeps you full for longer, leading to healthier food consumption overall.
Pasta and other carbs shouldn't necessarily be discarded either.
As the pendulum has swung away from demonizing fat, people have started to consider carbs the enemy. But carbs, especially whole grain carbs, have long been part of a healthy human diet.
As with most foods, the key is moderation. A recent long-term study found that people who got around 50% of their calories from carbs tended to live longest. Eating too many or too few carbohydrates were both associated with a higher risk of death.
There is some concern that particularly processed carbs (like those in candy or cookies) that are absorbed quickly may raise blood sugar in a dangerous way. But whole grain carbs and carbs from plants are essential sources of energy. Just don't forget to eat vegetables with your pasta.
During the years of fat avoidance, skim milk took off, but there are good reasons to opt for whole milk.
Whole milk is a fantastic source of calcium, protein, fat, vitamin D, and other nutrients. A recent study in the American Journal of Clinical Nutrition found that dairy fat doesn't seem to have a negative impact on cardiovascular disease or death rates.
Fatty oils can be healthy — and that's not limited to olive oil.
People tend to recognize that olive oil is healthy at this point, despite having a high fat content — it's healthy fat, after all.
But other oils that are similarly high in monounsaturated fat that can also be good choices for cooking, including peanut and sesame oil.
Potatoes aren't always thought of as a health food, but they are full of nutrients.
Potatoes fall under the healthy carb category, and they are packed with healthy components. They're great sources of potassium and vitamin C, and if you keep the skin on them, they can be good sources of fiber as well.
Butter's vindication is part of the rethinking of full-fat dairy.
To get away from butter decades ago, people started opting for artificial alternatives full of trans fat, which have turned out to be awful for your health.
As fats — including dairy fats — have been vindicated, it's become more and more clear that butter isn't necessarily bad for you. Again, moderation is key.
Even salt isn't as bad as anti-sodium proponents might have you believe.
Salt makes everything taste better. And it turns out the evidence against seasoning food is far less conclusive than dietary recommendations would have you believe.
A growing body of research indicates that for people who don't already have high blood pressure, salt consumption doesn't really seem to have much of an impact on health. There's even evidence that getting too little sodium might be connected to higher blood pressure, though more data is needed.
Perhaps the most useful thing is to be aware of how much salt we're eating in the first place. Processed foods that are packed with sodium aren't healthy for a variety of reasons, and those foods (and restaurant foods) make up 70% of the average person's sodium intake. Salt added to food being cooked at home and added at the table are only about 10% of average salt intake.
Avoid too much processed food, but don't feel bad about a sprinkle of salt on your home-cooked potatoes.
For the vast majority of people, gluten is just fine.
In recent years, "gluten-free" has become a marketing term attached to all kinds of foods, with gluten-free diets often cited by celebrities and other trend-makers.
But gluten simply refers to a mixture of proteins found in wheat, something humanity has eaten for thousands of years. For the approximately 1% of the world with Celiac disease, it can cause serious problems. A tiny percentage of other people may have some sort of non-Celiac sensitivity, where gluten makes them feel uncomfortable. But for the vast majority of us, gluten is totally fine.
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