The scientific basis for health information about caffeine
Caffeine intake during pregnancy and fetal growth
According to information published on March 25, 2021, pregnant women who consumed caffeine equivalent to 0.5 cups of coffee per day gave birth to smaller babies than those who did not consume caffeinated beverages.
The researchers found that there was a trend toward a reduction in infant size and lean body mass associated with mothers consuming less than 200 milligrams of caffeine per day.
The study.
analyzed data on more than 2,000 racially and ethnically diverse women at 8-13 weeks gestation in 12 clinical sites. All women were nonsmokers and had no health problems prior to pregnancy. From 10 to 13 weeks gestation, the women provided blood samples that were analyzed for caffeine and paraxanthine.
They also reported their daily consumption of caffeinated beverages (coffee, tea, soda, energy drinks) in the past week. Compared to infants born to women with no or minimal blood levels of caffeine, infants born to women with the highest blood levels of caffeine were found to be on average 84 grams lighter, 0.44 cm smaller, and 0.28 cm smaller in head circumference at birth.
Also, women who drank about 50 mg of caffeine a day seemed to have infants born 66 g lighter and 0.32 cm smaller in thigh circumference than infants born to women who did not consume caffeine.
As for the problem.
The researchers noted that caffeine constricts blood vessels in the uterus and placenta, reducing the blood supply to the fetus and possibly stunting growth.
Similarly, they believe that caffeine may disrupt stress hormones in the fetus, potentially exposing it to rapid weight gain after birth and the risk of obesity, heart disease, and diabetes later in life.
Gleason, JL et al. Maternal Caffeine Consumption and Metabolism and Neonatal Anthropometry in the NICHD Fetal Growth Study. JAMA Network Open. 2021 DOI: 10.1001 / jamanetworkopen.2021.3238
Characteristics of people who do not respond to acupuncture
As it turns out, caffeine consumption was the cause.
The article I referred to was a conclusion from a mouse experiment, so the level of evidence is not high, but it does show that pain changes after acupuncture are influenced by caffeine intake.
The researchers used 8- to 12-week-old male and female mice.
In some experiments, the animals were given drinking water supplemented with caffeine and Other mice were given water that did not contain caffeine.
The scientists induced acute inflammatory pain by injecting directly into the animals' left hind ankle joint. They induced chronic inflammatory pain via an injection into the left hind paw knee joint. In other experiments, mice were injected with caffeine or saline at specific acupuncture points.
Mice also received sham acupuncture, where needles were inserted into the same acupuncture points but not rotated (as during active treatment).
In the acute pain model, pain was reduced by 35% after acupuncture. In the chronic pain model, a low dose of 0.1 mg/mL caffeine blocked the effects of acupuncture, and a high dose of 0.2~0.5 mg/mL caffeine blocked the effects of acupuncture.
In a chronic pain model, a low dose of 0.1mg/mL of caffeine blocked the effects of acupuncture, and a high dose of 0.2~0.3mg/mL worsened the pain after acupuncture.
Scientists have shown that even low doses of caffeine may interfere with acupuncture. The scientists said that even low doses of caffeine could be shown to interfere with acupuncture, and that acupuncture would be more effective if caffeine intake was regularly reduced. This is what I was saying.
Fujita T, Feng C, Takano T. The presence of caffeine reversibly inhibits the analgesic effect of acupuncture. Scientific Reports 2017; 7: 3397.
Caffeine and Diet.
Dieting with caffeine-containing beverages. This was a fad a long time ago. I'll show you the evidence about it.
Here is some evidence about it.
About the evidence
In one study, 167 overweight or obese participants (BMI 25-40) took supplements containing kola nuts (192 mg/day caffeine) and mafan (90 mg/day ephedrine) or placebo. Participants were encouraged to eat a normal diet and exercise moderately, with the exception of limiting dietary fat to 30 percent of calories.
After six months, those in the treatment group lost significantly more weight (mean weight 5.3 kg) than those in the placebo group (2.6 kg) and showed significantly greater body fat loss. A product containing caffeine and glucosyl hesperidin (G-hesperidin, a flavonone glycoside found primarily in citrus fruits) reduced abdominal fat and BMI in a Japanese clinical trial.
In this study, 75 healthy overweight men and women (BMI 24-30) received one of five daily treatments for 12 weeks and maintained their normal lifestyle and eating habits. The five treatments were placebo and four formulations of 0, 25, 50, or 75 mg caffeine and 500 mg G-hesperidin.
Caffeine and G-hesperidin at 75 mg significantly reduced BMI by a mean of 0.56 vs. 0.02 for placebo. 50 or 75 mg caffeine and G-hesperidin significantly reduced abdominal fat compared with placebo, but G-hesperidin alone or only 25 mg caffeine had no significant effect on BMI or abdominal fat.
These findings indicate that high doses of caffeine may be responsible for the observed effects. Data from a 12-year prospective observational study was provided insight into the long-term association between caffeine intake and body weight.
For the study, researchers enrolled 18,417 healthy men and 39,740 healthy women in either a nurse health study or a health professional follow-up study.
On average, the participants gained some weight during the study, but during the 12-year follow-up, men who increased their caffeine intake gained an average of 0.43 kg less than those who decreased their caffeine consumption.
For women, the corresponding mean difference in weight gain was 0.35 kg less.
In a cross-sectional study, German adults who lost weight and maintained their weight loss (n = 494) were more likely than the general population (n = 2,129, average intake 3.35 cups/day), suggesting that caffeine may help maintain weight loss. However, further research is needed to confirm these findings.
Andersen T, Fogh J. Weight loss and delayed gastric content evacuation after a South American herbal preparation in overweight patients. J Hum Nutr Diet 2001; 14: 243-50.[ PubMed abstract ].
Lopez-Garcia E, Van Dam RM, Rajpasak S, Willett WC, Manson JE, Hu FB. Changes in caffeine intake and long-term weight change in men and women. Am J Clin Nutr 2006; 83: 674-80.[ PubMed abstract ].
Icken D, Feller S, Engeli S, Mayr A, Muller A, Hilbert A, et al. Caffeine intake is associated with success in maintaining weight loss.Eur J Clin Nutr 2016; 70: 532-4.[ PubMed abstract ].
Exercise and caffeine.
In a recent article, I described caffeine and exercise.
I would like to introduce the details.
About the evidence
Many studies have shown that caffeine may improve performance in athletes by increasing endurance, strength, and power in high-intensity team sports activities when they ingest about 2-6 mg/kg body weight before exercise. If you weigh 154 pounds (70 kg), this dose is equivalent to 210-420 mg of caffeine. However, higher doses are unlikely to further improve performance and increase the risk of side effects. A review of the literature found that caffeine intake affects sport-specific performance (running, cycling, swimming, rowing, etc.) as measured by time trials.
Thirty of the 33 trials showed an improvement in performance, but the improvement was not statistically significant in half of them. In these studies, the improvement in performance ranged from a 0.7% decrease to a 17.3% increase, suggesting that caffeine is very helpful for some participants, but slightly impairs performance in others.
Factors such as timing of intake, mode or form of caffeine intake, and habituation to caffeine could also have accounted for the different effects on performance.
Mora-Rodriguez R, Parares JG Performance outcomes and undesirable side effects associated with energy drinks. Nutr Rev 2014; 72: 108-20.[ PubMed abstract ].
Institute of Medicine. Caffeine for mental task performance sustenance: a formulation for military operations External Link Disclaimer. Washington, DC: National Academy Press. 2001.
Analgesics and caffeine for the management of acute pain.
It was a paper published by Cochrane Review in 2012.
The use of caffeine was considered to have the same effect as analgesics.
This article discusses whether the use of caffeine in combination with analgesics is more effective in managing acute pain than analgesics alone.
The following is an introduction to the study.
Studies
Twenty studies (7238 participants) were included, but because some headache studies used different results, the number of participants in the analysis of the effects of caffeine was 4262, compared to 5243 previously.
Most of the studies used 100 mg to 130 mg of caffeine, paracetamol or ibuprofen, and the pain conditions examined were postoperative toothache, postpartum pain, and headache. There was a small but statistically significant benefit to using caffeine at doses above 100 mg. This was independent of pain status and type of analgesic.
About 5-10% of participants achieved a good level of pain relief (at least 50% of maximum in 4-6 hours) with the addition of caffeine, yielding an NNT of about 14 (evidence of high quality).
Conclusion.
The addition of caffeine (≥100 mg) to standard doses of commonly used analgesics provides a small but significant increase in the proportion of participants experiencing good levels of pain relief.
Derry CJ, Derry S, Moore RA. Caffeine as an analgesic adjunct for acute pain in adults. Cochrane Database of Systematic Reviews 2014, Issue 12. art. No.: CD009281. doi: 10.1002 / 14651858.CD009281.pub3.
Interventions with Work and Caffeine Intake
For those who work in shifts, the environment is often poor, with long hours and working day and night. Under such circumstances, injuries and mistakes due to human error are bound to occur.
In order to avoid this, there is a study that suggests that caffeine can be used to avoid drowsiness. In order to avoid this, what if we could use caffeine to make people sleepy?
The study
Thirteen studies were included in the study.
None of them measured injury outcomes.
Two trials measured errors, and the remaining trials used neuropsychological tests to assess cognitive ability. The trial assessing the effect on errors found that caffeine significantly reduced the number of errors compared to placebo.
Estimates of pooled effects on performance by cognitive domain showed that caffeine improved concept formation and reasoning when compared to placebo.
However, there was no beneficial effect on language function and language skills.
One study comparing the effects of caffeine with napping found significantly fewer errors in the caffeine group. Other trials comparing caffeine with other active interventions (e.g., napping, bright light, modafinil) found no significant differences.
There is a high risk of bias against the validity of the concealment of allocation in trials and the presence of selective outcome reporting.
Conclusion.
Caffeine may be an effective intervention to improve the performance of shift workers, but no trials are available to assess its effects on injuries. Results are largely derived from studies with younger participants under simulated conditions, and the extent to which findings can be generalized to older workers and real-world shift work is unclear. Based on the current evidence, there is no reason why healthy individuals who are already using caffeine within the recommended levels should not improve their alertness and stop doing so. Assessing the relative effectiveness of caffeine against other potential measures should be the focus of future research.
Kale K, Edwards PJ, Felix LM, Blackhall K, Roberts I. Cochrane Database of Systematic Reviews 2010, No. 5. Number: CD008508. doi: 10.1002 / 14651858.CD008508.
Limiting Caffeine and Alcohol to Improve Meniere's Disease
What is Meniere's disease?
It is estimated that about 200 out of every 100,000 people suffer from Ménière's disease. When the cause cannot be identified, it's called Meniere's disease.
If there is a known reason for its onset, it is called Meniere's syndrome.
Patients complain of dizziness, hearing loss, pressure in the ears, and tinnitus as the main symptoms. Currently, there is no standard treatment for Meniere's disease, and treatment options include diet, medication, and surgery.
In the first place, the syndrome is thought to be caused by a disturbance in the amount or composition of endocrine fluid (endolymph) in the inner ear.
Dietary salt intake can affect the concentration of electrolytes in the blood, which in turn can affect the composition of the endolymph. It is thought that reducing salt intake may inhibit a contributing factor to seizures. This is thought to be the case.
Caffeine and alcohol consumption can cause vasoconstriction (constriction of blood vessels), which can lead to a decrease in blood supply to the inner ear. It is believed that this is the case. Many doctors recommend diet as a first-line treatment because it is a relatively simple and inexpensive option.
So, is there any benefit in limiting it? About that
What about studies?
We did not identify any studies that meet the selection criteria for the review.
Conclusion.
There is no evidence from randomized controlled trials to support or argue for restriction of salt, caffeine or alcohol intake in patients with Meniere's disease or syndrome.
Hussein K, Mardin L, Schilder AGM. Restriction of salt, caffeine and alcohol intake for the treatment of Meniere's disease or syndrome. Cochrane Database of Systematic Reviews 2018, Issue 12. 10.1002 / 14651858.CD012173.pub2.
