Sahil A. Desai, Mercer University College of Pharmacy
Consuming red meat has been shown to cause a higher risk of premature death  and the intake of processed red meat may be more likely to cause coronary heart disease, stroke, and/or diabetes.  Meats are stated to be rich in the pro-oxidants heme iron, nitrates, and nitrites which can cause oxidative damage and inflammation in different organs.  According to the American Cancer Society (ACS)  and American Heart Association (AHA) , both unprocessed and processed red meat can increase the risks of cancer and heart disease, respectively. It was recommended that substituting white meat and fish for red meat can reduce the risks of disease development.
|Mortality from different causes associated with meat, heme iron, nitrates, and nitrites in the NIH-AARP Diet and Health Study: population based cohort study |
|Design||Population-based, prospective cohort; N= 536,969|
|Objective||To determine the correlation of various types of meat intake and their associated compounds with overall and cause specific mortality|
|Study Groups||Divided into 5 groups based on average total red meat intake, g/1000 kcal:
|Methods||National Cancer Institute Diet History Questionnaires (DHQ) were sent out to American Association of Retired Persons (AARP) members aged 50-71 from six states (California, Florida, Louisiana, New Jersey, North Carolina, and Pennsylvania) and two metro areas (Atlanta, Georgia; and Detroit, Michigan). These questionnaires collected information on participant’s usual consumption of foods and drinks and portion sizes over the previous 12 months. Exclusion criteria included individuals who moved out of the study areas before returning the questionnaire; members with prevalent cancer, heart disease, stroke, or diabetes before study entry; and those who had 10 or more recording errors on questionnaire.
The meats were differentiated into four categories of unprocessed red meat that included beef, pork, hamburger, and steaks. Processed red meats were defined as bacon, ham, beef cold cuts, hot dogs, and sausages. Unprocessed white meat included unprocessed chicken, turkey, fish, and canned tuna. The final group was processed white chicken which was cold deli poultry, low-fat sausage, and low-fat hot dogs made out of poultry. Meat-associated compound calculations were based on frequency of meat consumption and using established database measurements from published studies and reports.
Follow ups were conducted by confirming the survival status of the patient via Social Security Administration agency statistics and a centralized database used to view causes of death.
|Duration||16 year follow up from return of baseline questionnaire|
|Primary Outcome Measure||Mortality from any cause during follow ups|
|Secondary Outcome Measure||Mortality mediation analysis based on heme iron, nitrate, and nitrite|
*compares the Group 5 hazard ratio vs. Group 1 hazard ratio
|Adverse Events||Common Adverse Events: N/A|
|Serious Adverse Events: N/A|
|Percentage that Discontinued due to Adverse Events: N/A|
|Study Author Conclusions||Mortality risks from all causes were elevated as consumption of both processed and unprocessed red meats increased. Heme iron, nitrate, and nitrite and other lifestyle choices were suggested for these increased rates. Supplemental data with hazard ratios showed a lower risk of mortality when substituting white meat, more specifically unprocessed white meat.|
Of concern from this study was the higher proportion of mediation caused by nitrates, substantiating the claim that pro-oxidative compounds other than heme iron play a role in poor health outcomes. Social history, lack of physical activity and reduced fruit and vegetable intake may contribute to certain diseases and death but family history of cancer and use of hormone replacement therapy were not accounted for within the results. Although correlation exists between red meat consumption and increased mortality, baseline characteristics were based on participant response. This is a cause of concern to the analyzed data as this data is more sensitive to bias and less accurate than objective measures.
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 Etemadi A, Sinha R, Ward MH, et al. Mortality from different causes associated with meat, heme iron, nitrates, and nitrites in the NIH-AARP Diet and Health Study: population based cohort study. BMJ. 2017;357:j1957.