Research recently released by the British Medical Journal , a renowned academic-medical journal in the United Kingdom, brought encouraging data. The work links daily caffeine consumption (between three and four cups of coffee) to a lower chance of developing cardiovascular problems and strokes. In this study, a statistical analysis of 218 surveys carried out over the years was carried out. He showed that the risk of heart disease is 19% lower in those who drink this recommended dose of coffee per day. In the case of stroke, this rate drops to 30%.
COFFEE HELPS PREVENT DISEASES
In healthy people, of any age, drinking three to four cups a day can reduce the risk of some diseases, such as:
- heart diseases;
– Parkinson’s and Alzheimer’s disease;
– obesity;
– diabetes;
– gallstones;
– some types of cancer (colon and rectum, liver);
- depression.
There are scientific studies that link moderate coffee consumption to improved liver function, increased immunity, better school performance (due to greater ability to concentrate). Coffee is also indicated as an adjunct in the cognitive-behavioral treatment of alcoholics, as it helps maintain remission of alcohol consumption.
WHEN COFFEE SHOULD BE AVOIDED
Even with so many benefits, pregnant women and people with the problems mentioned below should not regularly consume cups of coffee, unless under medical advice.
– gastritis;
– gastroesophageal reflux disease;
- peptic ulcer;
– generalized anxiety disorder;
– panic disorder;
– ischemic disease.
The United States nutritional guidance guide, Dietary Guidelines for Americans, used as a reference in several countries recommends that daily coffee intake should not exceed eight cups or 400 mg of caffeine.
Keep reading to better understand how coffee can be beneficial to your health as a whole, through a detailed review study published by Scielo:
Coffee is one of the most important raw materials in international trade. It is also one of the most appreciated drinks in the world, not only for its organoleptic characteristics, but also for its stimulating effect. New lines of research have highlighted other chemical compounds, also present in coffee, in addition to caffeine, suggesting potential beneficial and protective effects on the health of consumers of this drink.
The chemical composition of the green coffee bean is quite complex. During the roasting process, several chemical reactions also occur, through which they degrade and/or form numerous compounds. It is estimated that roasted coffee beans contain more than 2000 chemical compounds, some of which have known biological activities (adverse and/or beneficial). Therefore, the effects of coffee consumption will depend on the quality and quantity of the chemical compounds ingested, with moderate consumption normally described as ingesting 3 to 5 daily doses of coffee (approximately 150-300 mg of caffeine/day).
However, the chemical composition of the drink is quite variable and largely depends on the coffee species used, the most common being Coffea arabica (around 70% of world production) and Coffea canephora var. robust (more than 25%). These two species differ from each other in terms of their organoleptic, physical and chemical characteristics. The aroma and flavor of Arabica coffee are more appreciated than Robusta, and is therefore more commercially valued. Robusta coffee resists pest attacks more easily during its cultivation and is especially used to increase the body and foam of some drinks, as well as for the production of soluble coffee. Chemically, these species are differentiated by their content in different components: caffeine (double the amount in Robusta coffee), minerals, phenolic compounds, trigonelline, amino acids, biogenic amines, diterpenes, fatty acids, sterols, β-carbolines, among many others.
In addition to the influence of the coffee species, the type of processing to which the green beans are subjected (dry, wet or mixed, decaffeination), the degree of roasting and grinding, as well as the method of preparing the drink (filter, espresso , coffee maker, boiled, etc.) and the respective volume, will also contribute to the variation in the chemical composition of the final drink.
Finally, the frequency of intake, eating habits, lifestyle (alcohol and/or tobacco consumption) and individual genetic predisposition for the development of certain diseases may also influence the effects of coffee on the consumer's health.
COFFEE ACTION ON HEALTH
Coffee and stimulating effect
In addition to being a source of minerals, such as calcium, iron and magnesium, coffee contains a high dose of caffeine . This substance works by stimulating the central nervous system and presents excellent results both when used to improve concentration and mental work and as a muscle stimulant before physical exercise .
The main psychoactive component of coffee is, without a doubt, caffeine. The most notable behavioral effects occur after ingesting low to moderate doses (50-300 mg) of this compound, with an improvement in the consumer's cognitive and psychomotor performance (improvement in alertness, energy, ability to concentrate, performance in simple tasks, auditory vigilance, visual retention time and decreased drowsiness and tiredness).
The main mechanism of action of caffeine is due to its structural similarity with the adenosine molecule, a powerful endogenous neuromodulator, which inhibits the release of several neurotransmitters: glutamate, gamma-aminobutyric acid, acetylcholine and monoamines. Caffeine can bind to adenosine receptors (A1 and A2A), blocking them. In this way, the mainly inhibitory action of adenosine is prevented, with the effect of caffeine being, consequently, stimulating.
Moderate caffeine consumption does not generally appear to pose health risks. However, high doses can induce negative effects such as tachycardia, palpitations, insomnia, anxiety, tremors, headaches and nausea. It should be noted that these undesirable effects can also occur in some individuals sensitive to caffeine, even without consuming large amounts of coffee. It was also found that the anxiety caused by drinking coffee is more pronounced in individuals who are naturally anxious or who suffer from panic attacks.
Coffee and headaches
The effectiveness of caffeine in relieving headaches induced by caffeine withdrawal (which leads to cerebral vasodilation) reflects its vasoconstrictive properties at the central level.
Regarding other types of headaches, such as tension headaches, caffeine also appears to have an active role in relieving pain, with the effect depending on the dose ingested.
Coffee and Parkinson's disease
Parkinson's disease (PD) is caused by a severe degeneration of dopaminergic neurons in the substantia nigra of the brain, causing an inability to control voluntary movements and leading to tremor, akinesia, rigidity and postural instability. In general, epidemiological studies suggest that coffee consumption is inversely associated with the risk of PD, especially in males (dose-dependent relationship).
In a cohort study, men who consumed at least 3 to 4 cups of coffee per day had a 5-fold lower risk of developing PD than non-consumers. In another prospective study, men who consumed the amount of caffeine corresponding to a cup of coffee daily had a 50% lower risk of developing the disease, and no association was found in relation to the consumption of decaffeinated coffee.
Coffee and Alzheimer's disease
Alzheimer's disease is a neurodegenerative disease, which results in a progressive decrease in cognitive abilities, due to an increase in brain levels of the amyloid-β protein. In addition to caffeine, other compounds with antioxidant action found in coffee may play an essential role in protecting against this disease, reducing cellular oxidative stress through the neutralization of free radicals.
Coffee and depression/risk of suicide
It is known that moderate doses of caffeine have a positive effect on mood, disposition and cognitive performance due to its psychostimulant effect.
However, coffee consumption is closely associated with social habits that, in themselves, increase personal well-being.
Coffee and body weight
Several studies in humans suggest that coffee consumption induces weight loss by increasing thermogenesis and also an increase in lipolysis after ingesting caffeine , since there is an increase in energy expenditure after ingesting coffee or caffeine. There is evidence that this increase is dependent on the amount of caffeine ingested, and it has been estimated that an average intake of 6 cups of coffee daily causes an increase in daily energy consumption of approximately 100 kcal. Caffeine appears to be the chemical compound responsible for the thermogenic effect of coffee, as this was not verified after ingestion of decaffeinated coffee.
Coffee and gastrointestinal effects
It is not uncommon for coffee consumers to describe gastrointestinal discomfort after drinking this drink, and its consumption is not recommended in certain clinical situations.
5-Hydroxytryptamides (main components of coffee wax) seem to be partially responsible for gastric irritation, so some technological processes that reduce the waxy layer (polishing, steam treatment and/or decaffeination of green beans) may help to reduce this effect. With this objective, so-called "stomach -friendly coffees " were developed , aimed at more gastric-sensitive individuals, and are already sold in some countries.
Coffee and iron absorption
The inhibitory action of coffee on the absorption of non-haemic iron (of plant origin) is a nutritionally relevant situation, especially when this drink is consumed by iron-deficient or anemic individuals. Some studies indicate that drinking a cup of coffee after a meal reduces the absorption of non-hemic iron by 40%.
Coffee and renal system
A reduction in the risk of developing kidney stones by 10 and 9% was found with a daily consumption of 240 mL of coffee.
Despite the slight diuretic effect of caffeine, studies to date do not support the idea that moderate coffee consumption can cause dehydration.
Coffee and Type II Diabetes
Individuals who consume at least 6 to 7 cups of coffee per day appear to have a significantly lower risk of developing type II diabetes when compared to individuals who consume 2 cups or less.
Coffee and Blood Pressure
Hypertensive people can drink coffee normally, they just need to pay attention to the amount, as excessive consumption of the drink can raise blood pressure for more than three hours. Published studies do not allow us to effectively confirm whether or not coffee consumption is associated with hypertension, since coffee consumption is divided into small daily doses. However , moderation in consumption is recommended in individuals who are hypertensive, smokers and/or subject to stressful situations , as there is a general consensus that these groups will be more susceptible to the vasopressor effect of caffeine.
Coffee and cholesterol
Numerous studies have associated coffee consumption with an increase in serum levels of total cholesterol and LDL (low-density lipoproteins), an important risk factor for cardiovascular disease. This increase is not associated with the consumption of all coffee drinks, with their preparation method being crucial in the hypercholesterolemic effect. While the consumption of boiled, unfiltered coffee is responsible for an increase in cholesterol levels, it has been shown that the consumption of filter coffee has little or no association with serum cholesterol concentration.
Coffee and heart disease
Drinking one to five cups of ground or instant coffee per day has been associated with lower risks of arrhythmia, heart disease or failure, or stroke. Drinking two to three cups of any type of coffee every day has been linked to a lower risk of dying early or heart disease, according to data provided by UK Biobank through studies of more than 500,000 people over at least 10 years. .
Coffee and bones
Coffee/caffeine consumption has been associated, in some studies, with a slight negative effect on calcium balance, equivalent to a loss of 4 mg of calcium per cup of coffee consumed. However , its results are not consistent or conclusive. However, it is suggested that, especially older adults, ensure adequate intake of calcium and vitamin D and consume coffee in moderate doses.
Coffee and asthma
According to epidemiological studies carried out in this area, the probability of moderate coffee consumers developing the usual symptoms of asthma is, on average, 30% lower than non-consumers, with the beneficial effect being significantly dependent on the dose ingested. In addition to its bronchodilator effect, caffeine also reduces respiratory muscle fatigue.
Coffee and Cirrhosis
Experimental data suggest a potential beneficial effect of several coffee components on the liver, namely caffeine, cafestol, kahweol and polyphenols.
CONCLUSION
Coffee, consumed essentially for its stimulating effect and organoleptic properties, has a very diverse and complex chemical composition. Some of its components are responsible for various biological actions, many of which are not yet fully known and/or understood.
There is no evidence that moderate coffee consumption (3 to 5 cups daily) by healthy individuals is harmful. There are, however, some subgroups of the population that are more sensitive to the effects of caffeine, so in these cases, the consumption of this caffeinated drink should be avoided. However , recent lines of research point to a beneficial effect of coffee on the development of certain diseases, including: type II diabetes, asthma, alcoholic cirrhosis, certain types of cancer, Parkinson's disease and Alzheimer's.
For more details, follow the complete review article, which was a reference for this post:
Comentários