The DO-HEALTH study examines the effect of simple measures on the health of healthy adults aged 70+. The first evaluation shows no significant improvement in terms of bone fractures, leg and memory function through the intake of vitamin D, omega-3 fatty acids and strength training. However, certain groups could still benefit.
In 2030, one in three people in Europe will be over 65 years old. They all want to be able to enjoy life actively into old age. The most important prerequisite for this is maintaining physical and mental health.
Wanted: Simple and inexpensive prevention
The VITAL study from the USA published last year pointed out that vitamin D and omega-3 fatty acids cannot reduce the risk of new cancers and major cardiovascular events in 50-year-olds. The largest European age study DO-HEALTH now focuses on the effect of these supplements on the ageing process. The EU-funded project is led by Heike A. Bischoff-Ferrari, Professor of Geriatrics and Ageing Research at the University of Zurich, Clinical Director of the University Hospital Zurich and Chief Physician of the University Clinic for Acute Geriatrics at the City Hospital Waid and Triemli.
The first evaluation of the three-year data collection, now published by the international study team, showed no effects on leg and memory function or bone fractures. In predefined subgroups, the intake of omega-3 fatty acids and vitamin D showed greater benefits in reducing infections and systolic blood pressure compared to the control group.
Largest randomised, double-blind age study
For the study, the researchers recruited 2157 relatively healthy adults aged 70+ living at home, without significant pre-existing conditions. About half of them came from Switzerland, the rest from Austria, Germany, France and Portugal.
Participants were randomly divided into eight groups and received either none, one, two or all three of the following interventions: intake of one gram of omega-3 fatty acids per day, intake of 2000 International Units (IU) of vitamin D3 per day and/or a simple strength training session at home. Neither the study centres nor the subjects were aware of their group affiliation. The control groups received preparations without active ingredients (placebos) and carried out control training for joint mobility.
Over a period of three years, the seven European study centres carried out comprehensive annual full-day rounds to assess the health and functional status of the participants. In addition, detailed telephone interviews were conducted every three months. The study examined, for example, bone and muscle density, blood pressure, memory, walking speed and important biomarkers. Events such as new illnesses, infections, falls, visits to doctors and hospital stays were also recorded.
Significant positive effects only in subgroups
The results suggest that supplementation with vitamin D and omega-3 has no benefit for fracture risk, muscle and memory function in active people over 70 years of age with no previous illnesses. However, we suspect a link with infections, as Covid-19 is," said Bischoff-Ferrari.
Omega-3 fatty acids reduced the risk of infections by a total of 11 percent - especially in the upper respiratory tract (10 percent) and urinary tract (62 percent). Vitamin D lowered systolic blood pressure by 2.5 mmHg in men and the risk of any infection by 16 percent in the younger participants (70-74 years). ’Given the safety and affordability of the supplements and the high mortality from infection in older adults, these results have public health relevance,’ said Bischoff-Ferrari. The gender-specific effect of vitamin D on lowering systolic blood pressure also merits further investigation.
Getting the results right
The study team attributes the missing effects in terms of bone fractures, muscle function and memory function to the relatively good health status of the participants. Most of the participants were regularly active in sports and about half of them were so-called ’Healthy Agers’ without underlying diseases and without vitamin D deficiency. They were also all allowed to take 800 IU of vitamin D daily in addition to the study medication. The results therefore do not call into question the current recommendations of the BAG regarding vitamin D supplementation in older adults with vitamin D deficiency and risk of falling - nor the proven preventive effect of training programmes," says Bischoff-Ferrari.
Unique database for age research
The study team is now expecting the results of the DO-HEALTH interventions in terms of cancer prevention, cholesterol levels, cardiovascular diseases, falls, frailty and health care costs. Then we will be able to assess the comprehensive role of supplements in preventive geriatric medicine," says Bischoff-Ferrari. The extensive data and biobank of the DO-HEALTH study should also help in the future to assess the ageing process and disease risks for each person individually and early on, with the aim of personalised prevention. Ultimately, DO-HEALTH should enable more people to become healthy and active older," says Bischoff-Ferrari.
Heike A. Bischoff-Ferrari et all. for the DO-HEALTH Research Group. Effect of Vitamin D Supplementation, Omega-3 Fatty Acid Supplementation, or a Strength-Training Exercise Program on Clinical Outcomes in Older Adults. The DO-HEALTH Randomized Clinical Trial. JAMA, 10. November 2020. Doi: 10.1001/jama.2020.16909