Changes in plasma fatty acids and related biomarkers during transition to an exclusively plant- and fish-based diet in healthy adults

• Objective: The aim of this study was to examine the time scale of plasma fatty acid changes during transition to an exclusively plant- and fish-based diet in healthy individuals and determine whether there are associated alterations in arachidonic acid (ARA)-derived inflammatory mediators, estimated stearoyl coenzyme A desaturase (SCD) activity, and blood pressure. Methods: In pursuit of a religious fast, 36 adults abstained from eating poultry, meat, dairy products, and eggs, while increasing fish intake for 6 wk. Participants were assessed 1 wk before (W0) and 1 (WI) and 6 (W6) weeks after the diet change. Results: By W6, fasting plasma long-chain omega-3 polyunsaturated fatty acids (omega-3 LC-PUFAs); docosahexaenoic (DHA) and eicosapentaenoic (EPA) had increased (+67% and +73%, respectively; P <= 0.001), with early rise of DHA (+22%), but not EPA at W1.The omega-3 index (sum of DHA and EPA as a percent of total fatty acids) increased from 2.1% to 3.4%. ARA decreased progressively (W1, -9%; W6, -16%; P < 0.001). ARA precursors gamma-linolenic and dihomo-gamma-linolenic acids also decreased, without changes in the ARA-derived mediators prostaglandin-E2 and leukotriene-B4. Myristic acid decreased at W1 (-37%) and W6 (-40%). There was no consistent change in SCD indices. At W6, systolic and diastolic blood pressure had declined by 8 and 5 mm Hg, respectively (P <= 0.013). Conclusions: Shifting to a plant- and fish-based diet produces rapid and sustained increases in omega-3 LC-PUFAs and decreases the omega-6 PUFA ARA and its precursors, consistent with a cardio-protective profile. The rapid response suggests that these biomarkers may be useful for assessment of diet interventions. 

Subject headings

MEDICIN OCH HÄLSOVETENSKAP  -- Hälsovetenskap -- Näringslära (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Health Sciences -- Nutrition and Dietetics (hsv//eng)

Keyword

Fatty acid profile

Fasting

Cardiovascular disease

Polyunsaturated fatty acids

Inflammatory mediators

Blood pressure

Publication and Content Type

ref (subject category)

art (subject category)