The first diet was invented by a funeral director
Funeral Director William Banting (new tab) invented the very first diet in 1863. People used to say “I am banting” when they were on his diet.

All plants contain all amino acids
There's this never-ending debate whether vegans can get enough protein and whether said protein provides the full spectrum of amino acids.
Turns out, all plants contain all amino acids, including the 9 essentials.
The only real difference is that their levels vary slightly. Generally speaking, beans have less methionine and grains have less lysin. Hence, as long as we eat a good mix of plants, we most likely get all important amino acids in adequate levels.
If you want to be sure, try to eat an extra 0.1 - 0.2 g protein per kilogram body weight.

Flaxseeds should be grinded right before eating
Whole flaxseeds may pass through your intestine undigested leaving all the omega-3 fatty acids and phytochemicals unabsorbed.

Chocolate and peppermint relax the esophageal sphincter
Another one I learned during my SIBO therapy.
There are a couple of foods that relax the esophageal sphincter which can increase acid reflux, especially chocolate and peppermint.

Starchy foods retrograde while cooling down increasing their resistant starch content
Starches are made up of long chains of glucose which are the main building blocks of carbohydrates. Your body breaks them down into glucose resulting in blood sugar spikes.
Resistant starch on the other hand is also a carbohydrate, but also considered a type of fiber. They are resistant to digestion and thus pass through the intestines without being broken down.
By cooling down starchy foods, those normal starches retrograde into resistant starches, making it a more healthy meal overall.

One should limit water intake shorty before and after meals
Drinking too much shorty before, during or shortly after meals can influence your digestions and lower nutrition absorption.

Nutmegs are not nuts
Another one of those cases where the naming makes no sense.
The word nutmeg comes from the Old English nut, meaning hard seed or fruit, and meg, which is a shortened form of muge, meaning musky.
Nutmegs are acutally the dried seeds of the nutmeg fruit.

Slow eating has multiple health benefits
I've always been on the fast eating side, almost swolling foods without chewing at all. I knew that slow eating is a common mindfulness practice, but little did I know about the health implications of fast eating at that time.
Amongst others, eating slowly and chewing your food properly increases fat digestion and absorption of vitamins. It also reduces the likelihood of acid reflux and releases more insulin for better glucose control and therefore less glucose spikes after a meal.

Humans can't store protein
Learned it from Stanford's Professor Christopher Gradner (new tab).
At the end of the day, any excess protein is being turned into carbs and fat by taking off the nitrogen. This means, as long as we get enough protein through our diet - which actually is almost always the case - there's really no reason to take additional protein e.g. via protein shakes.
Apart from wasting money, it usually doesn't harm you though, as the nitrogen is turned into ammonia and then excreted by our kidneys.
But, if you already suffer from kidney problems, you should be cautious!

Grapefruits block enzymes that clear drugs
Another one from How not to die (new tab). This can be both positive and negative.
For example, if you use a painkiller, you can prolong it's effect by eating a grapefruit. But it's also very dangerous e.g. when you're taking multiple pills and they intefere with each other.

Chopping brokkoli 40 minutes before cooking preserves sulforaphane
I'm currently reading How not to die (new tab) by Michael Greger (new tab) and learned that brokkoli, which is super rich in sulforaphane, a substance that has many beneficial properties, needs to chopped 40 minutes before cooking in order to preserve it.