Thursday, November 14, 2013
Nigerian Scientists : The Benefits of Coffee
Ignite or rather a journey on coffee and health team is made up of Consultant Cardiologist at LUTH, Dr. D. A. Olusegun Joseph, a nutritionist at NIMR, Yaba, Dr. Bartholomew I. C. Brai, and Public health physician and Lecturer, Department of Community health and primary Care, College of Medicine, University of Lagos (CMUL), Dr. Kemi Odukoya.
Life expectancy is how long a person is expected to live. Life expectancy is also the expected number of years of life remaining at a given age. It is dependent on factors such as country, public health, medical care and life style including smoking, diet, and exercise.
More importantly is healthy life expectancy, also referred to as Health Adjusted Life Expectancy (HALE) or Healthy Life Years (HLY).
Olusegun-Joseph said the issue of ‘healthy life expectancy’ stresses that increases in life expectancy alone is not important.
The cardiologist said what is important is that people live longer lives in better health and that a major determinant of life expectancy and healthy life expectancy is healthier lifestyles.
He said chronic conditions are one of the main causes of reduced HALE and life expectancy. Olusegun-Joseph said a number of chronic conditions are directly or indirectly linked to lifestyle, especially unhealthy diet habits, use of tobacco, physical inactivity, and psychosocial stress
He said a major aspect of the lifestyle modification target is promotion of healthy eating habit, which includes consumption of healthy drinks.
However, recent articles point to coffee as one of the good, healthy beverage choices. Research over the past few years suggests that coffee consumption may protect against heart failure, type 2 diabetes, Parkinson’s disease, liver cancer, liver cirrhosis, gall bladder disease, among others.
The cardiologist further explained, “the antioxidant effect of coffee is becoming increasingly known. However, protective mechanism of coffee against a host of diseases may involve a lot more than anti oxidation. Coffee also exerts direct biological actions on the body, which may be protective against various diseases.
“Early studies suggest that the polyphenols in coffee (both caffeinated and decaffeinated) may modify key enzymes that improve intracellular signaling. Poor cell signaling may be a factor in cancer, diabetes, and many other ailments. Coffee compounds raise levels of detoxifying enzymes that protect against DNA damage. This may partly explain how coffee further lowers the incidence of related diseases such as cancer.
“DNA damage has also been found to predispose to premature aging. Researchers discovered that the phenolics have the direct action of dampening inflammatory activity. This may explain why coffee has been found to lower the levels of hsCRP and some other inflammatory markers.”
A 2008 study of 459 Japanese women revealed a significant, independent, inverse correlation between coffee consumption and serum C-reactive protein (CRP) levels. This relationship was also found by a group of researchers in America. CRP is a marker for systemic inflammation.
CRP has been shown to have predictive value for CVD, stroke, and death.
With all the supposed beneficial properties of coffee, are there any scientific impact on life expectancy/ HALE?
A May 2012 study by the New England Journal of Medicine found that, during the course of their study, coffee drinkers “who drank at least two or three cups a day were about 10 percent or 15 percent less likely to die for any reason during the 13 years of the study.
Coffee moderately reduces the incidence of dying from cardiovascular disease, according to a large prospective cohort study published in 2008.
A 2009 prospective study in Japan following nearly 77,000 individuals aged 40 to 79 found that coffee consumption was associated with a reduced risk of dying from cardiovascular disease.
Moderate consumption of this unique beverage has also been shown to reduce the risk of developing heart failure.
Besides, scientific studies have found that regular coffee consumption lowers the risk of type 2 diabetes by up to 67 per cent. This appears to result from reduced levels of blood glucose, increased insulin sensitivity, and decreased storage of both fat and carbohydrate.
Drinking coffee has been found to actually raise blood pressure briefly, right after consumption, linked to the effect of caffeine. Scientific studies, however, show that coffee’s compounds lower blood pressure over the long term, decreasing the risk of cardiovascular disease. This is believed to be a result of the beneficial action of chlorogenic acids on the arteries.
A meta-analysis of the available prospective studies from 1966 to 2011 shows that moderate coffee consumption is associated with lower risk of stroke. In the pooled analysis, habitual moderate coffee consumption was associated with decreased risk of stroke. Stroke risk in the high-consumption category showed a trend in the same direction, toward a reduction.
At the cellular level, just one cup of coffee inhibited platelet aggregation within one hour, regardless of its caffeine content. Regular coffee consumption improved inflammation and HDL (“good”) cholesterol, and decreased coronary calcification.
A 2011 randomised, controlled trial found that consumption of (caffeinated or decaffeinated) coffee produces specific improvements in the function of the liver and of adipocytes (fat-storing cells), both associated with a healthy metabolism.
Those drinking 4 cups of coffee daily exhibited a full 84 per cent lower risk of cirrhosis, according to a study in the Annals of Epidemiology. This is consistent with an earlier eight-year study of over 120,000 people that found that each cup of coffee daily lowered the risk of dying from cirrhosis by 23 per cent.
Caffeinated coffee reduced the incidence of gallstones and gall bladder disease in both men and women. Coffee consumption also reduces risk of developing various cancers. Moderate consumption protects against dental caries.
The cardiologist, however, said excessive intake, like any other substance, however, can be deleterious. He explained, “complaints of restlessness, agitation, awareness of heart beat in very high consumers greater than five cups of coffee/day.
“However, these are almost negligible in low consumers “Some people are very sensitive to caffeine’s stimulating effects, complaining of palpitation, restlessness, tremors. Such people are counseled to take with caution/ discontinue further intake.”
Olusegun-Joseph said coffee ingestion is contraindicated in patients with arrhythmias. He said coffee drinking is not intended to replace other healthy life style behaviors like exercise, smoking cessation, reduced salt and fatty meals!
Odukoya the health benefits of coffee have not been well understood in the past. “Coffee is often lumped with other stimulants like nicotine, hard drugs, and so on,” she said.
Oduloya said coffee has numerous health benefits as evidenced by many peer reviewed scientific studies but as with all things in life, moderation is key. “Moderate amounts of coffee consumption may play an important role in maintaining our health.”
The public health physician regretted that many health care practitioners (HCPs) dissuaded their patients from coffee intake but more recent research is showing evidence that coffee has many benefits to man’s health.
On what health care workers (HCW) in Nigeria think about caffeine and coffee, she said, “the major source of caffeine identified by health professionals was Coffee (73.3 per cent) and to an extent Cola nut (55.6 per cent) and carbonated drinks (50.2 per cent). About a third (28.4 per cent) indeed confirmed some analgesic drugs were also sources of caffeine to the body while a further 16.9 per cent also mentioned tea.”
So, is coffee really synonymous with caffeine? Odukoya said, “the study also showed that a significant proportion of health workers associated coffee consumption with poor health and tended to dissuade their patients from coffee intake…believing that they were helping their patients…”
A 2013 study in Sweden showed an inverse relationship between coffee intake and high-grade prostrate cancer.
A Norwegian cohort reported that coffee consumption was associated with a lower risk of breast cancer in lean women, but not in overweight women.
But Iowa women’s study found no significant association between consumption of caffeine and coffee and breast cancer risk according to categories of body mass index.
In 2011, a study done in the Republic of Korea showed that Cafestol- an important constituent of coffee has a potential to reduce renal cancer via its effect on apoptosis
In 1981, one study reported a relationship between coffee intake and pancreatic cancer. Since then many researchers have studied this association a little more closely. Meta analysis-in 2011 concluded that coffee is not related to pancreatic cancer.
Recent evidence shows that curacumin (diferuloylmethane) - a natural yellow compound in curry has important anti-cancer properties particularly liver cancer. When compared with coffee in rats, coffee was more effective at inhibiting hepato-carcinogenesis than curacumin.
A systematic review of the 20 epidemiologic publications reviewed, 17 found evidence that Coffee Consumption, can reduce risk of Type 2 diabetes, and improve indicators of normal glucose metabolism.
Three to four cups per day whether decaffeinated or regular was also associated with at least 25 per cent lower risk of type 2 diabetes compared to no coffee consumption.
Odukoya concluded, “as we speak, many more studies are being carried out and we’ll be sure to update you as more evidence is reported. However, evidence is still needed on effects of adding milk, sweeteners etc. to coffee and how this modifies its health effects. Also the effects of consuming coffee with different types of meals as may be done in many parts of the world including Nigeria.