Swagpp Bio Valley
2024-07-24 19:58 Shanghai
Beijing's fried noodles, Gansu's Lanzhou ramen, Shaanxi's pork buns, Henan's braised noodles, etc., basically every northern city has its own unique and catchy noodles; Southerners, on the other hand, prefer rice, and white rice or fried rice is often used as the staple food on the table, accompanied by three dishes and one soup, which together form a meal.
Whether it is rice in the south or in the north, rice or wheat, its essence is carbohydrates, and it has to be said that China is really a "big country of carbohydrates". However, in this era of advocating weight loss, carbohydrates often seem to be "thrown into the cold", and even at dinner parties, it is common to hear people say, "Sorry, I stopped eating staple foods after I have recently cut off carbon".
Source: Photo.com
Why have carbohydrates suddenly become the target of public criticism? Is it so hard that "eating carbs" = "ruining health"? But in fact, carbohydrates are really not the "root of all evil", and proper intake can even have the effect of prolonging life!
Previously, a research team from the Xiangya School of Public Health of Central South University found the most "long-lived" carbohydrate intake - when the daily dietary carbohydrate energy intake accounted for 53.7% of the total energy, the longevity-related protein Klotho in the serum reached the highest value, which can effectively fight aging and prolong life; If the carbohydrate intake is too low, it will "reduce life" on the contrary.
https://doi.org/10.3390/nu15183956
Serum Klotho levels are a biomarker of aging and are inextricably linked to longevity. The discovery of the Klotho gene dates back to 1997, when a study found that mice lacking the Klotho gene showed earlier aging and shorter lifespans, while overexpression of the Klotho gene extended the lifespan of mice. As a result, the researchers speculated that the protein encoded by the Klotho gene has anti-aging effects.
Based on this, more and more studies have begun to dig deeper into Klotho protein and its role. Klotho protein has a variety of important biological functions, including regulating phosphorus metabolism, alleviating oxidative stress, reducing inflammation, and regulating energy metabolism. In humans, Klotho protein levels decline significantly after the age of 40, and aging-related pathologies (such as Alzheimer's disease, chronic kidney disease, diabetes, etc.) exacerbate this trend.
The Klotho gene is located on chromosome 13 in humans
Considering the key role of this protein in aging, researchers tried to explore the influencing factors of Klotho protein, so as to formulate targeted anti-aging strategies.
Researchers have turned to carbohydrates because of the possible links between dietary interventions and aging and life expectancy, such as high-carb diets and an increased risk of diabetes, cardiovascular disease, and some age-related diseases, and low-carbohydrate diets (calorie restriction, restrictive fasting, etc.) that are associated with longer life and improved health.
The investigators collected 10,669 participants from the National Health and Nutrition Examination Survey (NHANES) and recorded serum Klotho levels as well as dietary carbohydrate intake. The latter was measured using a 24-hour dietary review method, in which the dietary density of carbohydrate intake was calculated as follows:
Carbohydrate energy supply ratio (% kcal) = intake (g/day) × 4 (kcal/g) / energy intake (kcal/day)
The average carbohydrate intake of all participants was 236.21 ± 96.82 g/day, and the average carbohydrate-to-energy ratio was 48.83 ± 11.24%. In addition, the median serum Klotho level was 801.30 pg/mL.
The results showed that for every 10% increase in dietary carbohydrate energy ratio, serum Klotho levels changed by 1.59% in the fully adjusted model.
The investigators found that serum Klotho levels were highest in the third quartile group (i.e., carb-to-energy ratio of 48.92-56.20% kcal) when all participants were divided by quartile. Compared with the third quartile, serum Klotho levels in the first, second, and fourth were decreased by 5.37%, 2.70%, and 2.76%, respectively.
Relationship between carbohydrate-to-energy ratio and serum Klotho levels
Further RCS analysis showed that there was a nonlinear inverse J-shaped relationship between carbohydrate energy supply ratio and serum Klotho level, with the highest inflection point of 53.71%/kcal.
In other words, when the carbohydrate-to-energy ratio in the diet reaches 53.71%, the Klotho content in the serum will also reach the highest value, so controlling the proportion of carbohydrate intake in the weekday diet at about 53.71% can lead to a longer life.
Before this inflection point, for every 10% increase in carbohydrate energy supply ratio, serum Klotho level also increased by 3%. But after the inflection point, the correlation between the two decreases and is not even statistically significant.
Therefore, it is not reasonable to completely cut off carbon or eat less carbs in daily life, and it may cost you a long life! But carb lovers should also control their diet a little, excessive intake can also affect health and longevity.
Dose-response relationship between carbohydrate-to-energy ratio and serum Klotho levels
After stratified analysis, this association was more significant in participants under 60 years of age, male, non-obese and without a history of diabetes. This is also a reminder to everyone: don't change when you are old or sick, everything you do now is laying the foundation for a long life in the future.
In summary, there is an inverted J-shaped correlation between carbohydrate-to-energy ratio and serum Klotho level, when the carbohydrate-to-energy ratio is controlled at 48.92-56.20%, serum Klotho will reach a higher level, that is, the carbohydrate-to-energy ratio is controlled within this range, which is also more conducive to delaying aging and prolonging life.
Unexpectedly, controlling the carbohydrate-to-energy ratio at about 53.71% is the most beneficial to longevity! This result is slightly subversive.
Source: Photo.com
According to the researchers, carbohydrates naturally occupy a very important position as the first of the three major productive nutrients. Dietary carbohydrates themselves can be a source of certain vitamins, minerals, and fiber, and some nutrients may have a positive effect on the expression of Klotho protein.
In addition, low-carb diets tend to inevitably reduce the intake of high-quality carbohydrates, such as fruits, non-starchy vegetables, and whole grains, and even alter the number and type of gut microbes, among other changes, which have the potential to reduce Klotho by modulating levels of inflammation and oxidative stress. That's why you shouldn't eat too few carbohydrates every day.
Of course, excessive carbohydrate intake can induce a variety of adverse physiological effects, including the accumulation of final glycation products, insulin resistance, lipid metabolism disorders, and stimulation of oxidative stress and inflammatory processes, all of which downregulate Klotho gene expression. As a result, an excessively high intake of dietary carbohydrates may be detrimental to healthy Klotho levels that fail to fight aging.
It's worth mentioning that the three major nutrients – carbohydrates, proteins, and fats – all play important roles in their respective roles and complement each other. Therefore, extreme control or excessive intake is not advisable, and balanced nutrition is king.
Resources:
Xiang L, Wu M, Wang Y, Liu S, Lin Q, Luo G, Xiao L. Inverse J-Shaped Relationship of Dietary Carbohydrate Intake with Serum Klotho in NHANES 2007–2016. Nutrients. 2023; 15(18):3956. https://doi.org/10.3390/nu15183956