The impact of dietary meat intake reduction on haematological parameters in healthy adults

Abstract

Meat is a rich source of dietary protein, fatty acids and micronutrients (1) many of which are involved in the process of blood cell production. In the UK, meat and meat products contribute up to 40 % and 37 % of average daily protein consumed by males and females respectively (2) . However, epidemiological studies have indicated an association between red and processed meat intake and an increased risk of developing cardiovascular disease (3) and certain cancers (4) , and people are being advised to reduce their consumption of these foodstuffs.This report, concerning the impact of dietary meat reduction on haematological parameters, is a sub-study of a wider intervention investigating the physiological effects of reducing red/processed meat intake. Twenty-four adults (15 F:9M, age 21-47y) participated in the sub-study. All were healthy, non-obese (18-28 kg/m 2 ) omnivores with a habitual consumption of ⩾4 portions of red and/or processed meat per week, (with ⩾3 of these being consumed as main meals). The study was conducted using a single group, nonrandomised design. Participants were asked to reduce their red/processed meat intake by 50 % over a 12-week period. Nutrient intake was assessed via 4-day diet diaries, and haematological parameters (including white cell (WCC), red cell (RCC) and neutrophil count, and haemoglobin (Hb)) were obtained via an antecubital venous blood sample, at recruitment, and weeks 6 and 12 of the intervention.Red/processed meat intake was lower during the intervention (partial eta 2 0·271; P < 0·005), but dietary folate, cobalamin, iron, zinc, copper and magnesium intakes were similar (P > 0·05 in each case). Over the intervention, a significant reduction in neutrophil count was noted (P < 0·001), with median count being 3·6[2·95-4·3] × 10 9 /l at recruitment, 2·25[1·83-2·88] × 10 9 /l at week 6 and 2·65 [2·13-3·08] l at week 12. This was accompanied by a decrease in WCC (partial eta 2 0·352; P < 0·001). Forty-eight percent of volunteers (8 F:4M) were neutropenic (<2 × 10 9 /l) with 54 % (9 F:5M) showing a neutrophil reduction ⩾1 × 10 9 /l (range 1-4 × 10 9 /l; Gp 1). Mean reduction in protein intake from red/processed meat of this group (−19·9 (17·9)g/d) was no different (P = 0·294) to those whose neutrophil count did not reduce by ⩾1 × 10 9 /l (Gp2; −12·8 (13·0)g/d). There was no difference in reported total energy and macronutrient intake between groups, and folate, cobalamin, iron, zinc, copper and magnesium intakes were also comparable. In the whole cohort, a reduction in Hb and RCC occurred over the intervention (partial eta 2 0·283; P < 0·001 and partial eta 2 0·263; P = 0·001 respectively). However, there was no association between a change in RCC and WCC (r = −0·002, P = 0·994), nor between a decrease in total dietary iron intake and Hb levels (r = 0·166, P = 0·437). Participants did not report any symptoms during the intervention suggestive of anaemia or neutropenia.Reducing red/processed meat intake in healthy omnivores resulted in a decrease in Hb, RCC, WCC and neutrophil...

Examining the role of systemic chronic inflammation in diet and sleep relationship

“…On the other hand, in line with previous literature ( Ali et al, 2017 ; Azadbakht and Esmaillzadeh, 2009 ; Chai et al, 2017 ; Ley et al, 2014 ), we observed positive associations with SCI biomarkers and (i) consumption of food groups that are abundant in unhealthy diets (such as processed and unprocessed red meat) and (ii) adherence to Western-style diets ( Khayyatzadeh et al, 2018 ; Silveira et al, 2018 ). It is well known that unhealthy diets are characterised by higher consumption of sugar, salt, refined grains and saturated- and trans-fatty acids ( Jacka, 2017 ; Marx et al, 2017 ) and, of special importance, saturated fatty acids, have been repeatedly shown to increase inflammatory markers ( Mu et al., 2014 ; Ruiz-Núñez et al, 2016 ).…”

Impact of increasing vegetarian availability on meal selection and sales in cafeterias

“…Providing US and UK participants with meat substitutes, recipes, and educational materials led to large reductions in meat consumption (13): a 40% reduction in red and processed meat (31), a 54% reduction in spending on meat (32), and a 70% reduction in meat consumed (33). These results are impressive but, unlike increasing vegetarian availability, are time-and resource-intensive; thus, they may not be scalable, and their effects can diminish over time (24,31). One paper found that meat consumption was 60% lower at the end of the intervention than at the baseline but that after 2 mo, the effect had decreased to 40% (31).…”

“…These results are impressive but, unlike increasing vegetarian availability, are time-and resource-intensive; thus, they may not be scalable, and their effects can diminish over time (24,31). One paper found that meat consumption was 60% lower at the end of the intervention than at the baseline but that after 2 mo, the effect had decreased to 40% (31). Reducing the serving size of meat portions reduced meat consumption by 13 to 14% (34,35); hence, increasing vegetarian availability combined with smaller meat portions could be a powerful combined strategy to reduce the mass of meat served by cafeterias.…”