Apparently, carbohydrates can be optimally fed to health and longevity.
Low-carbohydrate diets that replace carbohydrates with proteins and fats from plant sources are associated with a lower risk of death compared to carbohydrates that replace protein and fat from animal sources.
The observational study of more than 15,400 people found that diets with both low (70% energy) in carbohydrates were associated with an increase in mortality, while moderate consumers of carbohydrates (50-55% of energy) had the lowest mortality risk
The primary findings, confirmed in a meta-analysis of carbohydrate intake studies, including more than 432,000 people from more than 20 countries, also suggested that not all carbohydrates with low carbohydrate content seem equal – more animal protein and Eating fats from foods such as beef, lamb, pork, chicken and cheese instead of carbohydrates was associated with a greater risk of mortality. Alternatively, eating more vegetable proteins and fats from foods such as vegetables, legumes and nuts were linked to lower mortality.
Low-carb diets that replace carbohydrates with protein or fat are becoming increasingly popular as a health and weight loss strategy. However, the data suggested that animal-based carbohydrates with low carbohydrate content may be associated with a shorter total life span and should be discouraged. Instead, if someone opts for a low-carbohydrate diet, the exchange of carbohydrates for more vegetable fats and proteins could actually promote healthy aging in the long term.
To address this uncertainty, researchers began studying 15,428 adults aged 45 and older. 64 years after different socio-economic backgrounds. All participants reported that they used 600-4200 kcal per day for men and 500-3600 kcal per day for women, and participants with extreme (high or low) caloric intake were excluded from the analysis.
The researchers also assessed the association between total carbohydrate intake (categorized by quantiles) and all cause mortality after adjustment for age, gender, race, total energy intake, education, exercise, income level, smoking and diabetes.
Results showed a U-shaped relationship between overall carbohydrate inflow and life expectancy, with low (less than 40% of calories from carbohydrates) and a high (more than 70%) intake of carbohydrates associated with a higher risk of mortality compared with moderate intake (50-55% of calories).  The researchers estimate that from the age of 50 the average life expectancy was 33 years for people with moderate carbohydrate intake – 4 years longer than those with very low carbohydrate use (29 years) and 1 year compared to those with high carbohydrate consumption (32 years). The authors stress, however, that since diets were only measured at the start of the trial and six years later, dietary patterns could change in 25 years, the reported effect of carbohydrate consumption on the life cycle would be less certain.
step of the study, the authors performed a meta-analysis of data from eight prospective cohorts (including ARIC) with data from 432,179 people. This revealed similar trends, with participants whose overall diet was high and low in carbohydrates with a shorter life expectancy than those with moderate consumption.
In further analyzes investigate whether the source of proteins and fats is favored in carbohydrate-rich diets – plant based on animal or animal was associated with longevity, researchers found that replacing carbohydrates with proteins and fats from animal sources was associated with a higher risk of mortality than a moderate intake of carbohydrates. In contrast, replacing carbohydrates with plant food was linked to a lower mortality risk.
The findings showed observational associations rather than cause and effect. Given the evidence from other studies, the authors speculate that western types of diets that heavily restrict carbohydrates often result in a lower intake of vegetables, fruits and grains and lead to a greater consumption of animal proteins and fats – some of which have been implicated in stimulating inflammatory pathways, biological aging and oxidative stress – and could be a contributing factor to the increased risk of death. Although carbohydrate-rich diets (often in Asian and less economically advantaged countries) tend to be rich in refined carbohydrates such as white rice, they can also contribute to a chronically high glycemic load and poorer metabolic outcomes.
The authors noted some limitations, including that dietary patterns were based on self-reported data, which may not accurately reflect the food consumption of participants; and that their conclusions about animal sources of fat and protein may be less generalizable for populations that often have diets with high carbohydrates, but often consume fish instead of meat.
Based on these principles, moderate intake of carbohydrates (for example roughly 50% of the energy) is probably more suitable for the general population with a very low or very high intake.
The findings appeared in the Journal of The Lancet Public Health.
(This story has not been edited by Business Standard staff and automatically generated by a syndicated feed.)