For clear and radiant skin avoid these 5 Acne causing foods.
First I want to point out there are no foods that directly cause acne. Anyone telling you that don't know what they are talking about.

Acne is caused by blood Sugar problems (insulin resistance), chronic inflammation and oxidative stress. Many foods aggravate these conditions and can thus aggravate or even trigger acne. But what you eat is not the only thing that affects these conditions. For example, lack of sleep, breathing polluted air and stress can do the same.

Also please don't think you can cure Acne simply by cutting these 'foods that cause acne' from your diet. You just set yourself up to fail. There are many reasons for blood Sugar problems, chronic inflammation and oxidative stress. Diet is one and removing these foods from your diet is a big step towards clear skin.

Eating too much fat can cause acne
Eating too much fat is perhaps the biggest reason behind blood Sugar problems. With blood sugar problems I mean your blood sugar levels 'swing' too much. They rise too high and drop too low. This 'swinging' causes a cascading hormonal reaction that leads to: increased sebum production and blocked pores.

Fat has another nasty effect. Too much of it in the bloodstream slows down nutrient and oxygen transport to cells. In effect your cells won't get the nutrients and oxygen they need when you eat too much fat. This can also aggravate acne.

Foods that cause acne: Dairy products
Dairy products are probably the worst foods you can eat if you have acne.

First, dairy products are often high-fat; think cheese and ice-cream. As you learned too much fat can cause acne.

Second, the milk almost always comes from pregnant cows. The milk from pregnant cows contains hormones. Unfortunately your skin glands contain enzymes that convert these hormones into DHT (dihydrotestosterone) hormone. DHT boosts sebum production at skin gland. So the hormones in milk indirectly increase sebum production, which of course leads to acne.

Finally everybody is allergic to milk - whether we develop visible symptoms or not. The human digestive systems lacks the enzymes to properly digest milk from other animals.

Digestion simply means food is 'broken down' into individual nutrients. If digestion is not complete it means the body absorbs larger molecules (instead of single nutrients). The problem with this is that the body does not recognize these. Instead the immune system treats them as 'invaders' and attacks them. The medical definition for is 'digestive leukocytosis'

More acne causing foods: Refined carbohydrates
This is mainly about grains and refined sugars. Fruits, when eaten whole, are not a problem because the fiber in them slows down digestion of sugars.

First problems with refined carbohydrates and sugars is they cause blood sugar problems. Refined sugars enter the bloodstream quickly and spike up the blood sugar levels. Eating too much fat further aggravates the problem.

Second, there foods are refined to the point where they contain almost no nutrients. To digest these sugars and grains the body needs vitamins, enzymes and minerals and it has to take them from its reserves. Over time this can lead to deficiencies that may lead to acne and other problems. Whole grains are better in this sense.

Third, like milk, humans cannot digest grains. We don't have the enzymes to completely digest grains. It means that eating grains always causes allergic reaction (whether we notice the symptoms or not). Allergies always mean more inflammation and oxidative stress --> more acne.

Whole grains or refined, doesn't matter. Humans cannot digest either.

Caffeine for pimples
Caffeine is another substance you should remove from your diet. Primary sources of caffeine are coffee, tea (black and green), chocolate, sodas, energy drinks and some pain killers.

Caffeine causes two big problems. First it increases triggers the adrenalin glands to release stress hormones, which increases your stress levels. Too much stress is bad for your health and skin. There are studies linking stress to acne and almost every health condition.

Second, caffeine disturbs your sleep. Even if you can fall asleep after taking in caffeine it prevents the body to enter the deepest phase of sleep. This deepest sleep is especially important because during this phase the body does physical repair and detoxing. If the body cannot recover from the stresses of the day you can expect your health to decline and acne get worse.

Stay ways from processed foods
Rule of thumb; any food that comes from factory is bad for your skin. Humans evolved eating whole, unrefined foods in their natural state. You should do the same.

Processed foods are often highly refined, which makes them impossible to digest properly. As you know this leads to allergic reaction, inflammation and eventually acne.

Because processed foods are highly refined they have little taste left. To make them palatable food manufacturers add flavors, additives and other chemicals to 'trick' your taste buds. These chemicals always lead to allergic reaction.

Processed foods often contain lots of fat and refined sugars. Say hello to blood sugar and related (such as Candida) problems. This also makes them highly fattening. Excess belly fat directly leads to insulin resistance (blood sugar problems) and inflammation (fat cells produce inflammatory hormones).
Avoiding these 5 foods that cause acne is a big step towards clear skin.

For clear skin I recommend cutting out or significantly reducing these 5 acne causing foods from your diet. This may not be enough to cure severe and persistent acne, but it's a big step to the right direction.