Which behaviour change techniques within interventions to prevent weight gain and/or initiate weight loss improve adiposity outcomes in young adults? A systematic review and meta-analysis of randomized controlled trials.

Young adulthood is associated with the highest rate of weight gain compared with any other adult age group. This review evaluates the effectiveness of interventions with adiposity outcomes among young adults and identifies which behaviour change techniques (BCTs) are most effective. BCT utilization was assessed using Michie's 93-item BCT Taxonomy v1. Six electronic databases were searched for randomized controlled trials assessing change in adiposity in young adults (17-35 years) until December 2019; identifying 21,582 articles. Fifty-one studies were included. Meta-analyses for weight (n=19 studies), body mass index (BMI) (n=20 studies), and waist circumference (n=10 studies) demonstrated no significant between-group differences at ≤3 or >3 months. There were no differences between interventions focusing on weight loss or weight-gain prevention. Narrative synthesis showed significant between-group differences in weight change, favouring the intervention in 14/43 (33%) studies. In studies assessing BMI and waist circumference, this was 31% (11/36) and 25% (4/16). Two BCTs had a percentage effectiveness ratio >50% in weight loss interventions; social support (unspecified) and self-monitoring behaviour, and one in weight-gain prevention interventions; and goal-setting (outcome). Findings demonstrate initial potential for these types of BCTs and can help build cumulative evidence towards delivering effective, cost-efficient, and replicable interventions.

Hartmut Lichtenthaler: an authority on chloroplast structure and isoprenoid biochemistry.

We pay tribute to Hartmut Lichtenthaler for making important contributions to the field of photosynthesis research. He was recently recognized for ground-breaking discoveries in chloroplast structure and isoprenoid biochemistry by the Rebeiz Foundation for Basic Research (RFBR; http://vlpbp.org/ ), receiving a 2014 Lifetime Achievement Award for Photosynthesis. The ceremony, held in Champaign, Illinois, was attended by many prominent researchers in the photosynthesis field. We provide below a brief note on his education, and then describe some of the areas in which Hartmut Lichtenthaler has been a pioneer.