Eating more plant protein associated with lower risk of death

Credit: Maliz Ong

The largest study to examine the effects of different sources of dietary protein found that a high intake of proteins from animal sources - particularly processed and unprocessed red meats - was associated with a higher mortality rate, while a high intake of protein from plant sources was associated with a lower risk of death. Results from the study - which analyzed data from two long-term epidemiologic studies - appears in the August 1 issue of JAMA Internal Medicine.

05 aug 2016--"Overall, our findings support the importance of the sources of dietary protein for long-term health outcomes," says Mingyang Song, MD, ScD, a research fellow in the Massachusetts General Hospital (MGH) Clinical and Translational Epidemiology Unit (CTEU) and Division of Gastroenterology and corresponding author of the report. "While previous studies have primarily focused on the overall amount of protein intake - which is important - from a broad dietary perspective, the particular foods that people consume to get protein are equally important. Our findings also have public health implications and can help refine current dietary recommendations about protein intake, in light of the fact that it is not only the amount of protein but the specific food sources that is critical for long-term health."
While several studies have suggesting that substituting proteins for carbohydrates in the diet has several health benefits - including weight management, reducing blood pressure and other cardiovascular risk factors - the authors note, few studies have examined the specific sources of protein. Those that have were relatively small and based on one-time assessment of participants' diets. The current study analyzes data from the Nurses' Health Study (NHS) and the Health Professionals Follow-up Study (HPFS), which have compiled comprehensive health data on more than 170,000 participants since the 1980s. In addition to completing overall health questionnaires every two years, participants provide information on their dietary intake - specifically how often they consumed portions of particular types of food during the preceding year - every four years.
The researchers analyzed more than 30 years of data for NHS participants and 26 years of data for HPFS participants, totaling more than 3.5 million person-years. During those time periods more than 36,000 deaths were documented among study participants - almost 9,000 from cardiovascular disease, around 13,000 from cancer and about 14,000 from other causes. After adjustment for lifestyle and other dietary risk factors, a high consumption of protein from animal sources - any types of meat, eggs or dairy - was weakly associated with an increased rate of death, while high consumption of protein from plant sources - breads, cereals, pasta, beans, nuts and legumes - was associated with a lower mortality rate.
More careful analysis revealed that the association of animal protein intake with an elevated mortality risk only applied to participants with at least one factor associated with an unhealthy lifestyle - being either obese or underweight, heavy alcohol consumption, a history of smoking, or physical inactivity. In fact, the association disappeared in participants with a healthy lifestyle. Analysis based on specific sources of protein indicated that the animal-protein-associated mortality risk applied primarily to processed and unprocessed red meats, which include both beef and pork products, and not to protein from fish or poultry.
"While we expected we might find the associations to be weaker in the healthy lifestyle group, we did not expect them to completely disappear," says Song. "But when we looked deeper into the data, we found that - at similar levels of animal protein intake - those in the unhealthy lifestyle group consumed more red meats, eggs and high-fat dairy, while the healthy lifestyle group consumed more fish and poultry. So we suspect the different sources of animal protein between the two groups may contribute to the stronger results in the unhealthy lifestyle group."
He adds, "Our findings suggest that people should consider eating more plant proteins than animal proteins, and when they do choose among sources of animal protein, fish and chicken are probably better choices. Future studies should examine the mechanisms underlying the different effects of plant and animal proteins - along with different sources of animal proteins - on overall health."

More information: JAMA Intern Med. Published online August 1, 2016. DOI: 10.1001/jamainternmed.2016.4182


Provided by The JAMA Network Journals

Study of 55 million people adds further evidence that patients admitted to hospital at weekends have higher mortality

A systematic review and meta-analysis of hospital data worldwide, presented as this year's Euroanaesthesia meeting in Stockholm, adds further evidence that patients admitted to hospital at weekends have higher mortality than those admitted on weekdays. The study is by Dr Hiroshi Hoshijima, Tohoku University, Sendai, Japan, and colleagues.

02 jun 2014--The analysis included 72 studies from various world regions, covering 55,053,719 participants. The authors found that weekend admission was associated with increased morality of between 15% and 17% depending on the statistical technique used.

Subgroup analysis revealed that patients admitted during the weekend were at a higher risk of death than weekday admission in patients in almost all categories. "There are at least two potential explanations for our results. First, these differences reflect poorer quality of care in hospital at the weekend, and second, patients admitted on at weekend could be more severely ill than those admitted on at weekday. We believe that poorer care at the weekends is the much more likely explanation."

The only exception to this trend was for the patients who underwent surgery, with the authors saying the lack of association between postoperative mortality and weekdays being potentially due to the few numbers of studies (just 4 studies) specifically examining postoperative mortality.

Furthermore, the authors say that, in some patients who underwent selected high risk procedures, these patients could received a substantial proportion of their postoperative care in critical care units that are more likely to provide the same type of service at all times during both weekdays and weekends. This would therefore dilute any effect of increased weekend mortality in these post-surgery patients.

The authors conclude: "Our systematic review shows that weekend admission is associated with higher mortality compared with weekday admission."

Provided by European Society of Anaesthesiology

Study demonstrates link between appetite and elderly mortality

BEER-SHEVA, ISRAEL, 13 may 2009 – A new study by a Ben-Gurion University of the Negev (BGU) researcher reveals a linkage between elderly people's appetite and mortality rates, with those who report impaired appetite more likely to die sooner.

The study, published in the May issue of the Journal of Nutrition, Health & Aging, demonstrated a link between the Daily Activity Energy Expenditure (DAEE-- an accurate measurement of total physical activity), appetite and mortality among well functioning community-dwelling adults. Information on an elderly patient's eating habits may be important for health providers regarding risk for patient deterioration and mortality.

"These findings are important because they show how subjective appetite measurement can predict death, even when adjusting for health and many other variables," said Dr. Danit Shahar, a researcher with BGU's S. Daniel Abraham International Center for Health and Nutrition and Department of Epidemiology. "Past studies failed to show an association with survival. It was thought that decreased appetite may be an indicator or a result to other health problems, and that malnutrition, rather than low appetite was associated with mortality."

"Dietary Factors in Relation to Daily Activity Energy Expenditure and Mortality among Older Adults" analyzes data from the Health, Aging and Body Composition (Health ABC) study to demonstrate that higher DAEE is strongly associated with increased appetite, resulting in lower risk of mortality in healthy older adults. Using 298 older participants (ages 70-82 years) in the Health ABC study, researchers analyzed DAEE and dietary factors, including self-reported appetite, enjoyment of eating and intake assessed by the Block Food Frequency Questionnaire (FFQ) and Healthy Eating Index (HEI).

Participants who reported improved appetite were at lower risk for mortality. Similarly, participants who reported good appetite at baseline had a low risk for mortality. The results remained significant taking into account health status, physical activity, demographic and nutritional indices. Follow up was nine years.

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Shahar, D.R., B. Yu, D.K. Houston, S.B. Kritchevsky, J.-S. Lee, S.M. Rubin, D.E. Sellmeyer, F.A. Tylavsky, and T.B. Harris. "Dietary Factors in Relation to Daily Activity Energy Expenditure and Mortality among Older Adults." The Journal of Nutrition Health & Aging. May 2009; 13(5): 414-20.