Question: It's well known that sugar makes most people totally hyper and over-active andall around jumpy but then tere are some people (Like myself) that it sort of has the opposite affect on. (Too much sugar makes me sleepy). Also its the same with caffine, my brother and I both drink coffee and when I drink it it's like liquid energy and it keeps me up and happy all day but my brother drinks it right before bed because it makes him tired. Why does it affect different people in different ways how it does?

Wow.. that’s a lot of questions in one.

First and foremost: Sugar does not make you jumpy. There is no scientific evidence for it. It’s mostly something called ‘observation bias’; parents tend to rate their kid as more jumpy when they know the kid has had sugar.

There is a stronger argument for sugar making your sleepy. If you’ve learned about blood glucose and insulin you may already know that high blood sugar triggers the release of insulin, which lowers the blood sugar. Low blood sugar makes you sleepy. This is part of the reason for the ‘after dinner dip’; being sleepy after eating.

With caffeine, it’s a different story. Caffeine is a stimulant, which can affect people in different ways. For instance, the medication that calms down ADHD sufferers is an amphetamine, which is a powerful stimulant to people who don’t have ADHD.

Plus, you can get used to stimulants. If you have three cups of coffee every day, you’ll be buzzy the first few days, but then it starts having less of an effect. (It’s called ‘desensitization’ and it’s difficult to say five times in a row).

So, you’ve already made the observation that you and your brother react differently to caffeine. Maybe you could try and quantify the reactions of your classmates; bring a thermos of coffee and ask them to give you a number from 1-5 to show how buzzy it makes them. (of course, ask them how much they have in a day first).