Category: Caffeine

The amount of this drink that keeps you slender and lowers the risk of  type 2 diabetes.

Higher blood levels of caffeine might help people to stay in shape, plus reduces the risk of type 2 diabetes.

Previous studies have found that drinking coffee leads to weight loss and lowers the odds of diabetes and genetic evidence now supports the findings.

Caffeine has the ability to break down body fat, hence people with higher plasma caffeine concentrations tend to be slimmer and less likely to suffer from diabetes and obesity.

Observational studies suggest that drinking 3 to 5 cups of coffee a day is linked to lower type 2 diabetes and cardiovascular disease including coronary heart disease and stroke.

A cup of coffee normally has 70 to 150 mg caffeine, making it a very good source of the bitter substance.

However, observational studies can be influenced by other factors so it is hard to say if caffeine alone or together with other compounds in caffeinated foods and drinks have such effects.

The current study used a method involving genetic evidence to find out the effect of caffeine on body fat, type 2 diabetes, and cardiovascular disease.

The results indicate that genetically predicted higher blood levels of caffeine was associated with lower weight and body fat percentage (BMI).

The weight loss from caffeine led to a lower risk of type 2 diabetes.

Caffeine levels, though, had no strong effect on cardiovascular disease including heart failure, atrial fibrillation, ischaemic heart disease, and stroke.

Caffeine, due to its thermogenic effects, has been shown to improve metabolism, increase fat burning, and control appetite.

For instance, a 100 mg caffeine intake would increase energy expenditure by 100 calories per day which helps towards weight loss.

The authors wrote:

“Our Mendelian randomization finding suggests that caffeine might, at least in part, explain the inverse association between coffee consumption and risk of type 2 diabetes.

Randomized controlled trials are warranted to assess whether non-caloric caffeine containing beverages might play a role in reducing the risk of obesity and type 2 diabetes.”

The study was published in BMJ Medicine (Larsson et al., 2023).

Caffeine withdrawal symptoms can be avoided by coming off slowly and substituting non-caffeinated products.

As little as one standard cup of coffee per day is enough to produce caffeine addiction.

So, caffeine withdrawal symptoms can be experienced if you miss out on just the one cup.

The more caffeine is habitually consumed, the greater the withdrawal symptoms tend to be.

Research over 170 years has found that there are five main symptoms of caffeine withdrawal.

1. Headache is the most common of caffeine withdrawal symptom

One of the most common symptoms of caffeine withdrawal is a headache.

Caffeine causes the blood vessels in the brain to narrow, so stopping caffeine causes them to open up and increase the blood flow.

The increase in blood flow can be painful until the brain adapts to the new rate of flow.

2. Fatigue or drowsiness

Caffeine helps to block the neurotransmitter adenosine that leads to the feeling of sleepiness.

The more caffeine you habitually consume, the more drowsy you may feel without it.

High caffeine consumers are likely to experience a more severe level of caffeine withdrawal symptoms.

3. Low mood, including depression and irritability

Caffeine can often increase people’s mood through its blocking of the neurotransmitter adenosine.

People ingesting caffeine can experience enhanced well-being and energy.

Using caffeine has even been linked to reduced levels of depression by some studies.

One study found that women who drank two to three cups of coffee a day had a 15 percent reduction in depression risk (Lucas et al., 2011).

Those drinking four or more cups per day had a 20 percent reduced risk.

Other studies in men have also suggested that caffeine intake is linked to lower depression.

Naturally, then, stopping caffeine can lead to low mood, depression and irritability for a period.

This can last until the body becomes used to living without caffeine.

4. Caffeine withdrawal symptom: problems concentrating

Most people feel more alert after using caffeine.

Studies find that caffeine increases sustained attention and vigilance.

This is the kind of attention you need to keep doing a relatively routine task that is unchallenging.

That’s why it’s often so good at work: it keeps us plodding on through boring stuff that we’ve got to get through.

Caffeine boosts the activity of dopamine and norepinephrine — both of which are neurotransmitters which stimulate alertness, focus, blood pressure and heart rate.

The effect is is particularly strong for people who haven’t had enough sleep.

When first giving up caffeine, then, it can feel more difficult to focus on relatively routine tasks until mind and body become used to it being absent.

5. Flu-like symptoms of nausea, muscle pain or stiffness

For people who habitually consume a lot of caffeine, the withdrawal symptoms can be particularly painful.

These may include flu-like symptoms, such as muscle pain and stiffness.

Less common is experiencing nausea: the feeling of an upset stomach or even of being about to vomit.

Caffeine withdrawal symptoms research

The five caffeine withdrawal symptoms listed above were revealed by researchers who reviewed 63 studies conducted over 170 years.

They found that 50 percent of people got a headache during caffeine withdrawal.

Around 13 percent had a headache plus worse symptoms that affected their ability to work.

Professor Roland Griffiths, study co-author, said:

“Caffeine is the world’s most commonly used stimulant, and it’s cheap and readily available so people can maintain their use of caffeine quite easily.

The latest research demonstrates, however, that when people don’t get their usual dose they can suffer a range of withdrawal symptoms, including headache, fatigue, difficulty concentrating.

They may even feel like they have the flu with nausea and muscle pain.”

People experienced the worst of their caffeine withdrawal symptoms between one and two days after stopping, although it often started within 12 to 24 hours.

Professor Griffiths said:

“Despite more than a century and a half of investigation into caffeine withdrawal, doctors and other health professionals have had no scientifically based framework for diagnosing the syndrome.

Our goal was to critically review the literature regarding caffeine withdrawal to validate the symptoms and signs of illness associated with it, and to determine how often withdrawal produced clinically significant distress.”

Taper off to to avoid caffeine withdrawal symptoms

If you want to quit caffeine, the key is to do it slowly and substitute non-caffeinated products.

Professor Griffiths said:

“We teach a systematic method of gradually reducing caffeine consumption over time by substituting decaffeinated or non-caffeinated products.

Using such a method allows people to reduce or eliminate withdrawal symptoms.”

Some people get no caffeine withdrawal symptoms

Caffeine withdrawal symptoms may be at least partly down to our expectations about the effects of caffeine.

It’s little studied, but there’s a suggestion that if you don’t expect to get withdrawal effects, then you won’t actually get them.

That’s probably why some people report having no withdrawal symptoms when they give up caffeine.

So giving up may not be as hard as you think.

Caffeine may have no overall benefit

Once the caffeine withdrawal symptoms are over — if you get any — you may experience little difference between a caffeinated and non-caffeinated life.

Research finds that people feel no more alert or energised when regularly drinking coffee than when abstaining completely (Sigmon et al., 2019).

A week or two after giving up caffeine, people in the study felt roughly the same.

Measures of blood flow and electrical activity in the brain also differed little between when people took caffeine and when they were abstinent.

Dr Stacey Sigmon, study co-author, explained:

“In contrast to what most of us coffee lovers would think, our study showed no difference between when the participant was maintained on chronic placebo and when the participant was stabilized on chronic caffeine administration.

What this means is that consuming caffeine regularly does not appear to produce any net beneficial effects, based on the measures we examined.”

The study was published in the journal
Psychopharmacology (Juliano & Griffiths, 2004).