[A critical assessment of the relation between the food industry and health research].

Objective: To describe the influence of the food industry in health research, observing how funding influences health outcomes and the quality of the studies.

Method: We performed a systematic review in MEDLINE, Cochrane Library Plus and Scopus using the MESH "Food Industry", "Food-Processing Industry", "Biomedical Research", "Research Support as Topic", and the keywords "Industry Sponsorship" and "Funding Source". The quality was assessed using the PRISMA guidelines.

Results: We revised 1,506 articles and 10 were included; two reviewed the relationship between funding-outcomes and quality-outcomes; six focused on the funding-outcomes relationship; and the other two focused on methodological quality. Six showed that funding from the food industry resulted in more favourable outcomes for their products. No differences in quality were found in relation to the funding source, but those which did not declare their funding had a worse quality.

Conclusion: Studies funded by the food industry showed favourable results for their products. However, this fact did not affect the quality of the studies.