As a hair conditioner
Onion peel is also used as a conditioner. You can use the above-mentioned water on your hair after a shower as it will leave some soothing effect but dealing with the smell could be pretty impossible.
Reduces cholesterol
To reduce cholesterol level you can use onion broth for drinking on the daily basis, if the taste is unbearable then one can add honey or sugar to improve the taste. But one thing should be kept in mind that nothing can replace exercise. For better results drink this broth side by side with exercise.