11 votes

Did science backtrack regarding coffee causing dehydration?

Why it has been long assumed that caffeine or coffee is dehydrating? Because caffeine is a mild diuretic - it stimulates water excretion through the kidneys. But the amount of water you consume with ...
Jan's user avatar
  • 15.9k
6 votes
Accepted

How to reduce half-life of caffeine?

TLDR summary of what I found: diet-wise brassica vegetables, in particular broccoli seems to have this effect (but other vegetables that share P450 inhibitors in common with citrus fruits have the ...
the gods from engineering's user avatar
6 votes

Why does caffeine make me sleep better?

Caffeine Absorption Caffeine Capsules - 200mg - 84-120 minutes So maybe you took the caffeine, were already tired so you napped(2 hours or 120 minutes) just as it was kicking in full blown and ...
Pobrecita's user avatar
  • 2,965
5 votes
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ADD medication (Dexadrine) safe to drink with low-caffiene (Mountain Dew)?

Micromedex does not list any precautions or patient educations notes for Dexedrine and caffeine. However both substances can have an effect on heart rate and blood pressure. Large amounts of caffeine ...
TheChinBurglar's user avatar
5 votes
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What is the amount of caffeine in the human body over time?

Caffeine is readily absorbed, with up to 99% absorbed within 45 minutes of ingestion.[1] The mean half-life in healthy individuals is 5 hours, although this varies widely between individuals, ranging ...
Carey Gregory's user avatar
  • 9,872
5 votes
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Why does caffeine raise your blood pressure when it's a diuretic?

Caffeine increased plasma renin activity by 57 per cent, plasma norepinephrine by 75 per cent and plasma epinephrine by 207 per cent. Urinary normetanephrine and metanephrine were increased 52 per ...
Graham Chiu's user avatar
  • 13.3k
5 votes
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Should people with tachycardia avoid caffeine?

A regular caffeine consumer will likely develop a partial or complete tolerance to many caffeine effects and side effects, including increased heart rate. Tolerance develops within few days of regular ...
Jan's user avatar
  • 15.9k
4 votes
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Research into caffeine that wears off quickly

According to https://www.ncbi.nlm.nih.gov/books/NBK223808/ caffeine spreads readily throughout the body, including the brain, and has only few things that influence its metabolisation positively or ...
Philip Klöcking's user avatar
3 votes
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Does caffeine have any distinct biological effects to adrenaline?

According to a case report about a 24-year old woman (PubMed Central), in agoraphobia, during a panic attack, the sympathetic nervous system is activated, which results in adrenaline release, which ...
Jan's user avatar
  • 15.9k
3 votes
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How does coffee affect blood sugar levels?

As a type 1 diabetic I have noticed even black coffee can have an effect on blood sugar. Coffee( the caffeine really) increases your blood epinephrine (adrenaline) levels. Adrenaline has the same ...
Parker McA's user avatar
3 votes

Can drinking alcohol release stored caffeine?

Caffeine is not stored in the body. For a normal person, peak concentration of caffeine in the bloodstream is reached between 30 minutes and 2 hours after consuming it. It's then metabolized with a ...
Mark's user avatar
  • 2,056
3 votes

Is Moderated Caffeine Good? (if so how much and how often)

If you take coffee daily, you no longer get a boost from it after about a week, but rather, you're just staving off the harsh withdrawal symptoms, not to mention over time it will physically change ...
Jonathan's user avatar
  • 151
3 votes
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Definition of "healthy adult" when interpreting FDA recommendations

I haven't been able to find a source that identifies what specific set of studies the FDA used to make this determination, and didn't immediately find a more detailed report the one linked here which ...
Bryan Krause's user avatar
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2 votes

Does caffeine reduce mass gaining by accelerating metabolism?

Answer: No Summary Metabolic effects of caffeine may vary depending on whether one is 'naive' to caffeine (infrequent user) or 'accustomed' to caffeine (daily user). Metabolic effects may also vary ...
John's user avatar
  • 1,104
2 votes
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Risks of Caffeine Powder

Caffeine comes from coffee beans, but it can also be synthesized in a laboratory. Caffeine has the same structure whether it’s in Coffee, Energy Drinks, Tea or pills/powder. Caffeine dosages should be ...
John's user avatar
  • 1,104
2 votes

How can caffeine cause nausea?

There are some conflicting results concerning the effect of caffeine on nausea. One study 1 reported that caffeine withdrawal is associated with nausea and vomiting which might suggest that caffeine ...
S.Victor's user avatar
  • 905
2 votes

What is the amount of caffeine in the human body over time?

This study correlated blood pressure and caffeine, and it showed that the body regulated after 4 days of consumption, therefore if you goal is to measure blood pressure, keep in mind tolerance ...
Jonathan's user avatar
  • 151
2 votes
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Getting rid of caffeine addiction

A paper in Psychopharmacology reviews studies of caffeine withdrawal symptoms and concludes that these symptoms "meet the bar" for being clinically proven withdrawal symptoms: headache, fatigue, ...
Kate Gregory's user avatar
  • 3,919
2 votes
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Does L-theanine increase caffeine's half-life?

The mechanism of action of L-Theanine is not quite well understood and at some degree recent studies find themselves in contradictory with the results, nevertheless I think the essencial is this ...
program's user avatar
  • 488
2 votes

How to avoid the diuretic effect of caffeine or green tea?

Caffeine intake is associated with increased urination, but controlled studies (e.g., here and here) demonstrate fairly rapid adaptation and no chronic diuretic effect. For most people, if you want ...
De Novo's user avatar
  • 3,178
2 votes

How much caffeine intake a day is still safe for health?

I have found an article published in November 2017 that states: "Evidence supported consumption of ≤400 mg/day in adults is not associated with overt, adverse effects." Link to the article: https://...
bart's user avatar
  • 151
1 vote

If I get COVID-19, can I still drink coffee?

Similarly to Graham Chiu, I could not find any relevant articles on PubMed. I performed searches linking viral disease and caffeine, but most were related to viral hepatitis. Instead, I decided to ...
Roby Vicary's user avatar
1 vote
Accepted

If I get COVID-19, can I still drink coffee?

At the very least, coffee (caffeine actually) can can have a complex interaction with pain medication. Caffeine can actually enhance the pain-relief effects of some medications, like aspirin, which is ...
the gods from engineering's user avatar
1 vote

If I get COVID-19, can I still drink coffee?

A search on Pubmed, and Google has found no data to support the assertion from the Viriginia Government that coffee drinking is deleterious to your health when you have the Covid-19. Unless they ...
Graham Chiu's user avatar
  • 13.3k
1 vote

If I get COVID-19, can I still drink coffee?

To some people, caffeine is a diuretic. You want to stay as hydrated as possible during any illness to give the body what it needs and promote a fast recovery. Since caffeine is a diuretic (to some ...
Tyler M's user avatar
  • 144
1 vote
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Is there a standard about maximal caffeine concentration for synergistic painkiller preparations?

According to the U.S. Food and Drug Administration (FDA), 2017: The GRASE dose for caffeine is established in the Stimulant Final Monograph as 100-200 mg not more often than every 3-4 hours. ...
Jan's user avatar
  • 15.9k
1 vote

Stomach ache after drinking tea

One of the possible solutions might be to try decaf tea. Although decaffeination also reduces the amount of polyphenols to some extent, in many cases there is still a lot of them left. The reduction ...
Lucky's user avatar
  • 2,833

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