Earl Grey Side Effects – How Much is Too Much?

I think we can all agree that Earl Grey tea is absolutely delicious.

But how much is too much? Are there any disadvantages? And what the heck is Earl Grey Intoxification?

Let’s examine some of the potential side effects of drinking Earl Grey tea.

Table of Contents

Earl Grey Tea Ingredients

Typically, Earl Grey combines black tea and bergamot oil.

However, this can change between different Earl Grey blends. And with no strict recipe, anything from the tea base to the ingredients can deviate from the original.

This article focuses on the classic black tea and bergamot oil version.

Is Earl Grey Okay to Drink Earl Grey Every Day?

Yes, it’s safe to drink Earl Grey every day. 

But like anything. Moderation is key!

Disadvantages of Drinking Earl Grey Tea Every Day

Caffeine Sensitivity

Earl Grey has a caffeinated black tea base. This can range anywhere from 40 to 120 milligrams per 230ml (8oz) cup. 

When consumed in reasonable amounts, the caffeine in Earl Grey tea is generally considered safe. 

However, drinking too much caffeine can pose problems. Symptoms will start with jitters and anxiety. Then, end with heart issues and even, depression.

Overconsumption of caffeine may also result in: 

  • Headaches
  • Sleep Issues
  • Caffeine Dependence
  • Irritability
  • Heartburn
  • Diarrhoea
  • Dizziness
  • Irregular Heartbeat
  • Increased Urination

If you’re worried about drinking too much caffeine, it might be time to switch to a decaffeinated Earl Grey. 

Or, to avoid caffeine altogether, opt for an Earl Grey with a herbal tisane base.

Caffeine-free Earl Grey options Include:

  • Rooibos Earl Grey
  • Honeybush Earl Grey
  • Lemon and Ginger Earl Grey
  • Lavender Earl Grey
  • Chamomile Earl Grey
  • Peppermint Earl Grey

Heavy Metal Accumulation

While tea is relatively healthy, your cuppa may contain trace amounts of heavy metals.

This includes:

  • Mercury (Hg)
  • Lead (Pb)
  • Aluminium (Al)
  • Arsenic (As)
  • Cadmium (Cd)

Research shows that environmental factors such as soil, fertiliser, geographical location, and weather conditions can all lead to the contamination of tea leaves.

The plant maturity, tea type, and steep time will also affect the transfer and accumulation of heavy metals in your drink. 

While the water and vessel used to prepare and brew your cup of tea may add to the toxic load.

According to this study, these levels are low enough to be considered safe. But experts recommend that you keep your consumption (of all teas) to under 5 litres per week.    

Luckily, black tea (like that found in Earl Grey), contains some of the lowest levels of these heavy metals. With Mercury and Cadmium registering as undetectable during testing.

In contrast, Chinese Oolong tea had some of the highest heavy metal levels recorded.

Leaching of Pesticides

Pesticides play an important role in the quality and protection of tea plants. 

But while these chemicals are regulated. Studies from 2011, 2014, 2020, 2021, and 2022 uncovered that some popular tea brands contained traces of banned substances. 

These pesticides, neonicotinoids, insecticides, and fungicides included:

  • Acetamiprid
  • Thiacloprid
  • Chlorfenapyr
  • Bifenthrin
  • Glyphosate

However, in this study, researchers concluded that the leaching of pesticides in black tea was low.

Pesticides from the study included:

  • Ethion
  • Endosulfan
  • Dicofol
  • Chlorpyrifos
  • Deltamethrin
  • Hexaconazole
  • Fenpropathrin
  • Propargite
  • Quinalphos 
  • Lambda-cyhalothrin

In small doses, these substances are mostly harmless. But over time this residue can accumulate. And the long term effects aren’t widely understood.

CBC Marketplace – Pesticides in Tea: Testing the Chemicals in Your Cup


Tea’s healthy, right? 

Well, your cup of Earl Grey might be harbouring a secret ingredient – plastic!

And for the first time in history, microplastics have been found in human lung tissue, blood, and stool

Of course, this isn’t solely down to tea bags. Microplastics are everywhere, including the water we drink and the air we breathe. But it’s certainly something to consider when choosing which Earl Grey brand to buy.

Luckily, tea makers in the UK (at least) are taking action. With big brands like Tetley and PG Tips (Unilever) signing up to the WRAP UK Plastic Pact – something that’s going international

While plastic-free tea brands like Clipper and Pukka are on the rise. 

And for fans of Twinings Earl Grey, the tea maker pledges to be plastic-free by 2025

If you can’t wait until then, it might be time to ditch the tea bag and opt for some loose-leaf Earl Grey. 

The BBC tested several UK tea bag brands to see which of them contained plastic.

Bleached Tea Bags

More chemicals, please. Said no one ever!

So why do some tea bags contain harmful chemicals like chlorine, dioxin, and epichlorohydrin

Well, it turns out tea makers use bleach to chemically treat tea bags. 

This chemical process not only turns the tea bag white. But coating it in epichlorohydrin improves the wet strength of tea bags.

If you’re anything like me, you’ve never given the colour of your tea bag a second thought. 

But maybe it’s time we did. 

Thankfully, tea brands like Clipper and English Tea Shop use unbleached tea bags.

Earl Grey Intoxification

Too much Earl Grey tea can be bad for you. But you have to drink a lot of it to suffer any ill effects. 

According to this case study, a 44-year-old man found this out the hard way. 

The man reportedly drank a whopping 4 litres (17 cups) of black tea a day for 25 years. 

But when he switched to Twinings Earl Grey, things took a turn for the worse. 

After one week of excessive Earl Grey consumption, he started experiencing stomach cramps. 

And after five weeks, the pain had spread to his hands and right calf. Soon, his vision became affected, along with distal paraesthesias in his extremities. 

After five months of testing, the man reduced his tea consumption to 2 litres of plain black tea per day. 

And he completely cut out Earl Grey tea from his diet.

His symptoms disappeared just one week after quitting the bergamot-flavoured tea. 

The report concluded that the reason for the man’s many ailments was due to the bergamot in Earl Grey tea. An ingredient that can interfere with potassium channels.

It also didn’t help that tea was the man’s sole fluid intake. 

Symptoms of Earl Grey Intoxification may include:

  • Muscle Cramps
  • Fasciculation
  • Distal Paresthesias
  • Eye Pressure
  • Blurred Vision

Earl Grey Tea Allergies

Bergamot isn’t the only ingredient in Earl Grey tea to think about. 

Some people can be allergic to tea. 

Albeit, like Earl Grey Intoxification, very rarely.

Common Causes Include:

  • Tannins
  • Caffeine
  • L-theanine

Tea Allergy Symptoms Include:

  • Respiratory Issues
  • Hives
  • Anaphylaxis

Less Severe Symptoms Include:

  • Bloating
  • Diarrhoea
  • Heartburn
  • Irritability
  • Stomach Cramps
  • Nausea and Vomiting
  • Skin Flushing
  • Itchiness

How Much Earl Grey Tea Should You Drink a Day?

As a rule of thumb, you should drink no more than four cups of Earl Grey per day. That’s around 24-32oz (710-950ml).

But this number depends on a multitude of factors. And a cup of Earl Grey tea may affect you differently from someone else. 

So, if you’re new to black tea, start with one cup of Earl Grey per day to gauge your black tea tolerance. 

Is Earl Grey Safe During Pregnancy?

Earl Grey tea contains both caffeine and tannins – two compounds linked to pregnancy complications.

Therefore, exposure to too much Earl Grey may increase the risk of the following:

  • Miscarriage
  • Low Infant Birth Weight
  • Sudden Infant Death Syndrome (SIDS)
  • Caffeine Withdrawal in Newborns

As such, research indicates that you should keep your daily caffeine intake below 200mg

Earl Grey contains around 40-120mg of caffeine per cup (8oz). 

So that’s around two to three cups of tea per day. But again, this can vary!

The caffeine content of Earl Grey will depend on a few factors:

Black tea also contains high levels of manganese

On their own, these levels are fine. In fact, this mineral helps build strong bones, among other things. 

But when combined with other sources of manganese (e.g. prenatal vitamins) it may result in toxic levels. And if taken in excess, it may hinder the neuropsychological development of your child.

To be on the safe side, you may prefer to drink Earl Grey with a herbal tea base (e.g. Redbush Earl Grey). 

Luckily, there’s a growing range of herbal Earl Grey blends to choose from.

But the NHS and FSA (Food Standards Agency) still recommend that you drink no more than four cups of herbal tea per day.

And this can also come with side effects. For example, premature labour.

According to the American Pregnancy Association, these are the herbal tea ingredients to avoid when pregnant.

Rated ‘Likely Unsafe’ or ‘Unsafe’
  • Cohosh (Blue & Black)
  • Liquorice
  • Pennyroyal
  • Roman Chamomile
  • Passionflower
  • Pau D’arco
  • Yohimbe
  • Ephedra
  • Dong Quai
  • Goldenseal
  • Saw Palmetto
Rated ‘Possibly Unsafe’
  • Aloe
  • Ginseng
  • Evening Primrose
  • Feverfew
  • Kava Kava
  • Senna

As always, if you’re concerned about drinking Earl Grey while pregnant, it’s best to consult with your doctor.

Is it Safe to Drink Earl Grey Tea When Breastfeeding?

Yes. Generally speaking, drinking black tea is safe when breastfeeding.

But experts recommend that you limit your caffeine intake to between 200mg (NHS) and 300mg (CDC) or below. 

But be aware. Your breast milk may contain traces of caffeine. And it may reduce the iron content of your breast milk by up to one third

While the amount of caffeine may be minimal (around 1%), infants and newborns take longer to process caffeine when compared to adults. 

This amount can also build up over time, causing noticeable side effects in nursing infants.

Signs to look out for include:

  • Trouble Sleeping
  • Restlessness
  • Fussiness
  • Irritability
  • Hyperactivity
  • Increased Bowel Movements

If you notice any of the above side effects, try limiting your caffeine intake. Or cut out caffeine altogether.

Other options include breastfeeding before caffeine consumption. And after drinking caffeine, wait at least three hours before breastfeeding.

Earl Grey Tea Side Effects

1. Medication Interference

The majority of the Earl Grey side effects come from the tea base. But several issues can also stem from the bergamot.

For one, bergamot can lower blood sugar levels. As a result, those who drink Earl Grey while taking diabetes medication should be cautious.  

Not only that, but bergamot can react with other medications, preventing them from pumping into the blood. 

For instance, medications such as fexofenadine are less effective when taken alongside bergamot. 

To avoid any adverse reactions, read the medication sheet and look for any potential interactions.

2. Muscle Cramps

Too much Earl Grey can also result in muscle cramps. 

This is caused by a compound in bergamot tea that can block potassium absorption. And it could be an issue if you have any underlying muscular problems.

One study recalled how a man suffered from muscle cramps and blurred vision after drinking too much Earl Grey tea (17 cups per day). 

The muscle cramps subsided when he stopped drinking Earl Grey tea. This suggests that if you ever overdo it, discontinue drinking Earl Grey until you feel better.

3. Poor Sleep

Earl Grey tea contains caffeine. As a result, it may disrupt your sleep.

And studies show that caffeine consumed up to six hours before bedtime can negatively affect sleep quality. 

Lack of sleep can also result in fatigue, impaired memory, depression, and a reduced attention span. 

While chronic sleep deprivation can increase the risk of obesity and poor blood sugar control.

If you’re suffering from any sleep issues, reduce your Earl Grey intake and monitor any changes.

4. Nausea

Tannins are what give your cup of tea that reddish brown colour. 

But when steeped for too long, they can produce a dry, bitter, and astringent taste. Something that can irritate the digestive system. 

And when consumed on an empty stomach, the tannins in Earl Grey tea may cause nausea. Especially when consumed in large quantities. 

To avoid feelings of nausea, try drinking Earl Grey tea with milk. Or, with a meal. 

5. Reduced Iron Absorption

The black tea in Earl Grey is full of phenolic compounds called tannins

Made up of large molecules, tannins easily bind with other molecules such as proteins, minerals, enzymes, carbohydrates, and minerals. 

For this reason, they’re often used in dyes and medicines. And because of their antioxidant properties, they have a lot of health benefits. 

But this ability to bind does come with its downsides. 

For one, tannins can block plant-based (non-heme) iron absorption. 

According to this study, those following a plant-based diet (vegans and vegetarians) are more susceptible to this side effect. 

But research shows, that unless you have an existing iron deficiency (e.g. anaemia), you needn’t be concerned. 

To limit the anti-nutrient effects of tannins, drink Earl Gey between meals. This gives your body time to absorb the iron from your food.

And, if you take iron tablets, it’s recommended to avoid drinking tea.

6. Oesophageal Cancer

Hands up if you like your Earl Grey tea piping hot?

Stop! You may want to let your brew cool before your next sip.

A recent study found that drinking tea at temperatures over 60°C (140°F) could increase your risk of oesophageal cancer.

Not to mention, burn your mouth, throat, and oesophagus. 

While another 10-year study of over 50,000 participants, suggested that it could more than double your risk.

Of course, it’s no news that drinking exceedingly hot drinks aren’t good for you. 

But as Cancer Research UK quite rightly points out, other factors (e.g. age, smoking, drinking, and eating habits) need to be taken into consideration. 

And that the research on this link to cancer is limited. 

Luckily, tea drinkers in the US and UK prefer their beverage under 60°C. Typically adding a splash of milk to cool their cuppa before consumption.

Confused? Here’s a full breakdown from Doctor Mike.

7. Stained Teeth

Like all good things in life, there’s usually a downside. 

Coffee, red wine, and of course, Earl Grey tea can stain your teeth.

And that’s thanks to tannins – the reddish brown pigment in your cup of tea.

But according to this study, all is not lost. 

Simply add milk to your cup of Earl Grey to avoid tarnishing your pearly whites.

Milk was found to significantly reduce tea induced staining. 

That’s because milk contains casein, a phosphoprotein that makes up 80% of the protein in cow’s milk. 

Researchers concluded that it’s this component (casein) that prevents black tea from staining your teeth. 

Gotta love science!

8. Headaches

It’s commonly thought that the tannins in Earl Grey tea cause headaches. But caffeine is more likely to be the culprit. 

And this study found that as little as 100mg of caffeine per day can trigger chronic daily headaches. 

However, it’s not all bad. 

Another study revealed that intermittent exposure to caffeine can serve as a mild analgesic for headaches.

The lesson here? Don’t overdo it!

9. Heartburn

Caffeine is great. It wakes you up, keeps you alert, and boosts your metabolism. 

But excessive caffeine consumption can have a negative effect. 

And while not exclusive to tea (coffee lovers beware), drinking too much Earl Grey can cause heartburn and acid reflux.

Caffeine can do this in two ways.

1. Relaxes the Lower Esophageal Sphincter (LES)

As part of this study, 12 healthy volunteers (6 men and 6 women) between the ages of 19-31 were single blind tested. The aim was to examine the effects of caffeine on the gastrointestinal system. After consuming caffeine (3.5 mg/kg), there was a notable change in the pressure of the LES and distal oesophagal contraction of participants. This relaxation of the sphincter allowed stomach acid to readily flow into the oesophagus, causing acid reflux.

2. Stimulates Gastric Acid Secretion (GAS) Production

Caffeine is a bitter-tasting compound. A study from 2017 found that this can induce gastric acid secretion (GAS), by triggering several type 2 bitter receptors (TAS2Rs) in the mouth and gastrointestinal tract. In turn, this increases the production of stomach acid.

According to this article, the caffeine in tea can also aggravate gastroesophageal reflux disease (GERD). 

GERD is a disease brought on by diet and lifestyle choices. And it affects up to 40% of US adults

However, this report concluded that there was no significant association between GERD and drinking tea overall. 

That said, they found demographics did play a factor. For instance, tea drinking in Asia showed an increased risk. While tea drinking in the Middle East had a lower risk of GERD. 

Therefore, if you have any pre-existing acid reflux symptoms, you should consider what tea base is used in your Earl Grey blend.

Is Earl Grey Tea Good or Bad For You?

While this all sounds a little scary, don’t worry! 

To experience any of these side effects, you’ll have to drink a lot of Earl Grey tea. 

And the health benefits of Earl Grey tea certainly outway any of the bad. 

But if you’re unlucky enough to suffer from any of the above. Cut down your tea and caffeine consumption. And if the symptoms persist, seek advice from a professional. 

When it comes to your health, it’s always better to be safe than sorry. No matter how tasty a cup of Earl Grey is.