Researchers compared general dietary advice with individualized dietary advice, along with an app that encourages users to follow a diet. Older adults with overweight and obesity benefited more from the individualized approach [1].
One size does not fit all
A good diet can help people stay healthy, even into old age. However, nutritional advice is designed for the average person and does not take into account the great variability between people’s dietary needs and preferences. Personalized nutrition approaches focus on this need to optimize the diet for the individual. Such personalized nutrition can also be considered a therapeutic approach to prevent or treat chronic diseases.
However, sticking to a strict, individual diet can be difficult for most people. The authors of the current study believe that digital tools can help and motivate people to follow the recommended diet. Therefore, they set up a trial to determine whether individual dietary interventions alongside a digital tool can influence the health of older adults with overweight and obesity.
Standard care versus individual diet
The study included 127 participants who were between 50 and 80 years old and had a BMI of at least 27. Participants had to have at least one risk factor, such as type 2 diabetes, hypertension, high cholesterol or sedentary behavior. The trial lasted 12 weeks and had a follow-up of 3 months.
The usual care group followed the Healthy Eating Plate (Harvard) and the Spanish Society of Community Nutrition dietary guidelines. These guidelines include recommendations regarding food groups, portion sizes, frequency of consumption and practical tips for designing menus.
They also attended online sessions to learn about prescribed dietary patterns, the use of food labels, seasonal shopping lists, meal plans and recipes, and sleep habits.
The precision diet group was instructed to follow a Mediterranean and mixed diet that included foods based on personal preferences, such as smoothies, fruit compotes, and whole wheat bread. These foods were specifically designed for this study and their ingredients were chosen to prevent age-related diseases. Also, only the calorie intake needs of the members of this group were assessed and they were present at visits to monitor compliance with the diet.
The precision diet group app was also specifically designed for this study with the needs of older adults in mind, and was easy to access and use. It included information about the assigned diet, reminders about follow-up visits, and motivational messages.
At the end of the study, participants completed a questionnaire about their food intake over 7 days, their physical activity, and their health status. They also took tests to assess their cognitive function.
Eat your way to better metabolic parameters
Analysis of the data obtained revealed that both groups experienced significant reductions in body weight, BMI and diastolic blood pressure after three months of dieting. However, the changes in the precision diet group were significantly greater than those in the usual care group.
There were also differences between groups. On average, participants who followed the precision diet intervention finished the study with reduced waist circumference, waist-hip ratio, fat mass, and systolic blood pressure compared to the usual care group.
The researchers also measured biochemical parameters, with both groups showing significantly better triglyceride and uric acid concentrations that were not significantly different between groups. Uric acid was used here as a marker of the anti-inflammatory effects of the dietary strategies, suggesting that both dietary approaches influence the inflammatory aging environment (inflammaging). However, there is a need to assess more inflammatory biomarkers to gain a better understanding of the underlying mechanisms behind these diets.
The precision diet group also had significantly lower total cholesterol and HDL-C levels and improved glycemic control and liver health markers, compared with both the baseline group and the usual care group.
The researchers measured total energy intake, but found no differences between the groups. However, the groups did differ in specific food groups, with carbohydrate, protein, and fiber levels significantly higher and lipids lower in the precision group.
The precision group also consumed less sodium but more sugar than the usual care group. The researchers point out that most of the sugars in the participants’ diet came from fruits, vegetables and dairy products. While free sugars should be limited in the diet, there is no evidence of adverse effects from consuming sugars that naturally occur in fruits, vegetables or milk. The results of this study also support this, as the researchers did not observe any negative effects with regard to glucose metabolism in participants in the precision group. They hypothesize that interaction with fiber and “other nutrients could positively influence the regulation of glucose homeostasis and metabolism” [2].
ADVERTISEMENT
Better diet, better quality of life
Based on questionnaires completed by participants after completing a 3-month study, members of the precision diet group improved their quality of life. Specifically, the precision diet group reported improvements in the vitality, body pain, and emotional role sections of the quality of life test. Both groups reported improvements in general health and physical function. Statistical analysis revealed many correlations between improvements in well-being and the metabolic changes observed in participants.
The authors believe that in the future, the use of big data and -omics technologies will enable even more personalized nutritional approaches. Such a strategy has the potential to better help develop nutritional approaches that allow for the prevention of diseases and the reduction of the effects of aging.
The researchers point out a number of limitations of the study. For example, baseline dietary intake was not assessed, there are potential biases due to self-reporting, the sample size is small, the mobile app was not assessed on its own (only in combination with the diet), and due to the nature of the intervention, it is not possible to conduct a double-blind study.
Literature
[1] Galarregui, C., Navas-Carretero, S., Zulet, MA, González-Navarro, C.J., Martínez, JA, de Cuevillas, B., … & Abete, I. (2024). The impact of precise nutrition on metabolic health and quality of life in an aging population after a 3-month intervention: a randomized intervention. The magazine about nutrition, health and aging, 28(7), 100289.
[2] Müller, M., Canfora, EE, & Blaak, EE (2018). Gastrointestinal transit time, glucose homeostasis and metabolic health: modulation by dietary fiber. Nutrients, 10(3), 275.