Ecologically sustainable nutriton for older adults (55+) with obesity.

In the Netherlands, there is a high prevalence of obesity among older adults
(55+) which is expected to rise in the coming years. Weight loss is crucial to
improving health outcomes for older adults, but it also poses the risk of
losing skeletal muscle mass. Therefore, dietetic advice for older obese clients
should consider the exacerbated age-related loss of skeletal muscle mass and
encourage the intake of extra proteins, alongside calorie restriction.
Currently, dieticians typically suggest an increase in animal-based proteins
due to their proven ability to stimulate muscle protein synthesis. On average
60% of the protein intake in the Netherlands is of animal-based sources.
However, animal-based proteins have a high ecological impact, while plant-based
proteins have a lower impact and offer numerous health benefits. To address
this, we developed a new dietary concept that aligns with current dietary
guidelines for older adults (55+) with obesity, incorporating a calorie
restriction and protein enrichment (towards 1.2 g/kg/d, minimum of 0.8 g/kg/d),
of which >=60% (minimum of 50%) (compared to current 40%) is plant-based
proteins and providing all essential amino acids.

Our primary objective of the feasibility study is to assess the acceptability
and feasibility of the developed 2EAT dietary treatment in older adults with
obesity.

The primary objective the main study (RCT) is to investigate whether a shift
towards more plant-based (>=60%) protein intake can be achieved in a calorie
restricted diet for three (primary) and six months in older adults (55+) with
obesity.

The secondary objectives of the study are to assess the effects of the 2EAT
dietary treatment on weight loss and skeletal muscle mass.

The exploratory objectives of the study are to assess the effect of the 2EAT
dietary treatment on physical health outcomes: muscle strength and physical
performance; body composition; metabolic bloodparameters; vitality and quality
of life; nutritional intake; behavioral changes; process of dietary treatment.

The study consists of two phases. In phase 1, a feasibility study will evaluate
the acceptability and feasibility of the 2EAT dietary treatment in older adults
with obesity. In phase 2, a randomized controlled trial of 6 months with two
parallel intervention groups will be conducted to investigate the effect of the
2EAT diet (>=60% plant-based protein) over time.

The 2EAT dietary intervention includes dietary counselling focussed on
behavioural change, and a diet with an energy restriction of 500 kcal and
increased protein intake based towards 1.2 g/kg/day (minimum of 0.8 g/kg/d), of
which >=60% (minimum of 50%) is plant-based. In the randomized controlled trial,
half of the participants will be randomized to the control dietary treatment
(40% plant-based protein).

The risks associated with participation are minimal. Assessments will be
carried out in a private controlled setting and interventions are guided by
trained dieticians and researchers. Participation in this study should benefit
older adults by improving body composition, providing social aspects and
personal health insights. The results of this trial will be used to support
evidence-based practice for more environmentally sustainable dietetic practice.