“It may be good for you,” says Dariush Mozaffarian, dean of the Friedman School of Nutrition Science and Policy at Tufts University. “I think we can say with good certainty it’s not bad for you.” (Additives are another story.)
After the link appeared between coffee intake and a reduced risk of heart failure in the Framingham data, Kao confirmed the result by using the algorithm to correctly predict the relationship between coffee intake and heart failure in two other respected data sets. Kosorok describes the approach as “thoughtful” and says that it “seems like pretty good evidence.”
Should you drink coffee? If so, how much? These seem like questions that a society able to create vaccines for a new respiratory virus within a year should have no trouble answering. And yet the scientific literature on coffee illustrates a frustration that readers, not to mention plenty of researchers, have with nutrition studies: The conclusions are always changing, and they frequently contradict one another.
The results of a new efficacy study on the AstraZeneca vaccine could pave the way for a Food and Drug Administration decision on whether the vaccine can be used in the United States.
The city of Miami Beach is under a curfew to try to mitigate crowds of rowdy spring breakers. And, the Biden administration is struggling to address the developing migration crisis at the country’s southern border.
Exercise training is a safe, effective and low-cost intervention for improving walking ability in patients with IC. Additional benefits may include improvements in QoL, muscle strength and cardiorespiratory fitness. Clinical guidelines advocate supervised exercise training as a primary therapy for IC, with walking as the primary modality.
However, evidence is emerging for the role of various other modes of exercise including cycling and progressive resistance training to supplement walking training. In addition, there is emerging evidence for home-based exercise programmes. Revascularisation or drug treatment options should only be considered in patients if exercise training provides insufficient symptomatic relief.
Peripheral artery disease (PAD) is caused by atherosclerotic narrowing of the arteries supplying the lower limbs often resulting in intermittent claudication, evident as pain or cramping while walking. Supervised exercise training elicits clinically meaningful benefits in walking ability and quality of life. Walking is the modality of exercise with the strongest evidence and is recommended in several national and international guidelines. Alternate forms of exercise such as upper- or lower-body cycling may be used, if required by certain patients, although there is less evidence for these types of programmes. The evidence for progressive resistance training is growing and patients can also engage in strength-based training alongside a walking programme. For those unable to attend a supervised class (strongest evidence), home-based or ‘self-facilitated’ exercise programmes are known to improve walking distance when compared to simple advice. All exercise programmes, independent of the mode of delivery, should be progressive and individually prescribed where possible, considering disease severity, comorbidities and initial exercise capacity. All patients should aim to accumulate at least 30 min of aerobic activity, at least three times a week, for at least 3 months, ideally in the form of walking exercise to near-maximal claudication pain.
“Aging is such a profound part of not only the human experience but all life on Earth,” says Salk Vice President/Chief Science Officer Martin Hetzer. “It’s one of the big, untapped opportunities in biomedical research, particularly around questions on what role exercise, nutrition and cognitive stimulation play in staying healthy throughout life. It is important not to forget that getting older also comes with benefits; we want to take a holistic view of human health at all ages and understand it from all angles.”
Scientists want to answer intriguing questions: Why are some people able to “age well,” trekking up mountain ranges or rafting through white water in their nineties, while others live just as long, disease-free, but grow inexplicably frail decades sooner? Worse yet, why does advanced age sometimes diminish cognitive ability or even lead to dementia?
In numerous diseases, age itself is the major risk factor. Cancer, Alzheimer’s, heart disease and many other afflictions become profoundly more likely the older we get. Aside from extending our life spans, scientists want to know how we can also extend our health during advanced age. What is emerging from research is that aging–loosely defined as a systems-wide deterioration of our cells, organs and genetic material that results in disease or damage–is a collective and complex process in the body.
In this cross-sectional study of 5364 couples consisting of employees and spouses (or domestic partners) undergoing an annual employer-sponsored health assessment, 79% of the couples were in the nonideal category of a CV health score. This within-couple concordance of nonideal CV health scores was associated mostly with unhealthy diet and inadequate physical activity.
The study included 10 728 participants (5364 couples): 7% were African American, 11% Hispanic, 21% Asian, and 54% White (median [interquartile range] age, 50 [41-57] years for men and 47 [39-55] for women). For most couples, both members were in the ideal category or both were in a nonideal category.
Concordance ranged from 53% (95% CI, 52%-54%) for cholesterol to 95% (95% CI, 94%-95%) for diet. For the CV health score, in 79% (95% CI, 78%-80%) of couples both members were in a nonideal category, which was associated mainly with unhealthy diet (94% [95% CI, 93%-94%] of couples) and inadequate exercise (53% [95% CI, 52%-55%] of couples). However, in most couples, both members were in the ideal category for smoking status (60% [95% CI, 59%-61%] of couples) and glucose (56% [95% CI, 55%-58%]).
Except for total cholesterol, when 1 member of a couple was in the ideal category, the other member was likely also to be in the ideal category: the adjusted odds ratios for also being in the ideal category ranged from 1.3 (95% CI, 1.1-1.5; P ≤ .001) for blood pressure to 10.6 (95% CI, 7.4-15.3; P ≤ .001) for diet. Concordance differed by ethnicity, socioeconomic status, and geographic location.
Herd immunity occurs when a significant portion of a population becomes immune to an infectious disease, limiting further disease spread.
Disease spread occurs when some proportion of a population is susceptible to the disease. Herd immunity occurs when a significant portion of a population becomes immune to an infectious disease and the risk of spread from person to person decreases; those who are not immune are indirectly protected because ongoing disease spread is very small.
The proportion of a population who must be immune to achieve herd immunity varies by disease. For example, a disease that is very contagious, such as measles, requires more than 95% of the population to be immune to stop sustained disease transmission and achieve herd immunity.
How Is Herd Immunity Achieved?
Herd immunity may be achieved either through infection and recovery or by vaccination. Vaccination creates immunity without having to contract a disease. Herd immunity also protects those who are unable to be vaccinated, such as newborns and immunocompromised people, because the disease spread within the population is very limited. Communities with lower vaccine coverage may have outbreaks of vaccine-preventable diseases because the proportion of people who are vaccinated is below the necessary herd immunity threshold. In addition, the protection offered by vaccines may wane over time, requiring repeat vaccination.
Achieving herd immunity through infection relies on enough people being infected with the disease and recovering from it, during which they develop antibodies against future infection. In some situations, even if a large proportion of adults have developed immunity after prior infection, the disease may still circulate among children. In addition, antibodies from a prior infection may only provide protection for a limited duration.
People who do not have immunity to a disease may still contract an infectious disease and have severe consequences of that disease even when herd immunity is very high. Herd immunity reduces the risk of getting a disease but does not prevent it for nonimmune people.
Herd Immunity and COVID-19
There is no effective vaccine against coronavirus disease 2019 (COVID-19) yet, although several are currently in development. It is not yet known if having this disease confers immunity to future infection, and if so, for how long. A large proportion of people would likely need to be infected and recover to achieve herd immunity; however, this situation could overwhelm the health care system and lead to many deaths and complications. To prevent disease transmission, keep distance between yourself and others, wash your hands often with soap and water or sanitizer that contains at least 60% alcohol, and wear a face covering in public spaces where it is difficult to avoid close contact with others.
But on its own, “BMI [body mass index] remains a strong independent risk factor” for severe COVID-19, according to several studies that adjusted for age, sex, social class, diabetes, and heart conditions, says Naveed Sattar, an expert in cardiometabolic disease at the University of Glasgow. “And it seems to be a linear line, straight up.”
For starters, the blood of people with obesity has an increased tendency to clot—an especially grave risk during an infection that, when severe, independently peppers the small vessels of the lungs with clots
Immunity also weakens in people with obesity, in part because fat cells infiltrate the organs where immune cells are produced and stored, such as the spleen, bone marrow, and thymus, says Catherine Andersen, a nutritional scientist at Fairfield University. “We are losing immune tissue in exchange for adipose tissue, making the immune system less effective in either protecting the body from pathogens or responding to a vaccine,” she says.
The impact extends to the 32% of people in the United States who are overweight. The largest descriptive study yet of hospitalized U.S. COVID-19 patients, posted as a preprint last month by Genentech researchers, found that 77% of nearly 17,000 patients hospitalized with COVID-19 were overweight (29%) or obese (48%). (The Centers for Disease Control and Prevention defines overweight as having a BMI of 25 to 29.9 kilograms per square meter, and obesity as a BMI of 30 or greater.)
Diabetologia (Sept 8, 2020) – Insomnia with objective short sleep duration has been associated with an increased risk of type 2 diabetes in observational studies [27, 28]. The present MR study found strong and suggestive evidence of a causal association of insomnia and short sleep duration, respectively, with increased risk of type 2 diabetes.
The present study verified several previously reported risk factors and identified novel potential risk factors for type 2 diabetes. Prevention strategies for type 2 diabetes should be considered from multiple perspectives on obesity, mental health, sleep quality, education level, birthweight and smoking.