Toxins

Just a PSA:

If someone is telling you something about your health, and they talk about "toxins", they are most likely full of shit.

e.g. "You should not eat any food and drink a bunch of lemon juice to cleanse your body of toxins."

It's a totally hand-wavey term that requires no understanding and is easy to repeat.

Ask them to be specific (and find sources to verify). If they can't, promptly disregard and reevaluate anything that person has ever told you.

Being full of shit is a lifestyle.