Celebrity nutritionist shares key signs that you need to reduce your caffeine intake

Celebrity nutritionist Sarah Carolides has revealed the signs that you're having too much coffee.

We all love a cup of coffee. Whether it's to perk us up in the first thing morning or to drink while chatting with friends, the National Coffee Association says that around 517 million Americans have a daily cup of joe.

One thing you may have noticed about coffee is how different people react in different ways to it.

Why is this, I hear you ask? Because of our metabolisms.

Millions of Americans are frequent coffee drinkers (Getty Stock Image)

"There are a couple of genes that mean you are either a fast metabolizer or a slow metabolizer of coffee," Sarah, Head of Nutrition at Zooki, explained to UNILAD.

She went on to say that you probably don't need a genetic test to establish if you're a fast metabolizer or not as you probably already know.

Sarah went on to share: "[If] I had a coffee now, after two o'clock, I will be up to at least midnight. I'm a slow metabolizer.

"My husband is fast metabolizer. He can have a double espresso after dinner and be out five minutes later, and it doesn't interrupt his sleep at all."

Sarah Carolides is a celebrity nutritionist and Head of Nutrition at Zooki (Supplied)

According to Sarah (who has worked with Hollywood actors, influential business leaders, and high-profile politicians), those with fast metabolisms could benefit from having up to four coffees a day and see health improvements in 'all sort of areas', such as improving cardiovascular health.

Meanwhile, those whose bodies have a slower rate of turning food and drink in energy could see negative affects of drinking this much – such as making your skin more dehydrated.

In regards to working out if you're having too much coffee full stop, Sarah wants people to ask themselves: "Are you in control of your coffee, or is it in control of you?"

There are ways to know if you need to cut back on coffee (Getty Stock Images)

She continued: "If you wake up in the morning and you go, I cannot function until I've had my double espresso or whatever, you know what, I want you to give it up for a while and see what happens.

"Do you start getting the headaches? Do you start feeling really awful? Because if that's that's also a sign that you're not metabolizing it well and it's affecting you in the wrong way."

Sarah concluded: "If you can come off coffee easily, and doesn't affect you. You feel you still feel fine, then you're in control."