Fasting, traditional diets lower allergy, autoimmune disease risk
What and how much you eat determines the immunological response and susceptibility to disease more than your genes.Updated: Sep 15, 2019 14:46 IST
Fasting and going back to traditional diets can help lower allergies and autoimmune disorders that have shot up over the past three decades, according to an international study from Germany.
What and how much you eat determines the immunological response and susceptibility to disease more than your genes, found the large animal study published in Nature Communications, which demonstrated fasting and traditional diets with whole grains and vegetables score over “western” diets high in sugar and fat.
The study found that disease onset and prevalence was dramatically accelerated in mice on western diets, while caloric restriction protected them from lupus, an autoimmune disorder in which immune cells attack multiple cell components in its own body. Lupus cases have gone up three times in the last three decades.
“In a nutshell, these results suggest that western diet enhances disease and disease-related phenotypes, while calorie restriction protects against them. More importantly, it shows the adverse effect of corrupt DNA can be altered by changing the dietary regimes,” said study co-author Dr Yask Gupta, a post-doc researcher at the Lübeck Institute of Experimental Dermatology, which led the study.
A western diet was defined as diets high in sucrose (sugar) and fat such as red meats, burgers, pizzas, and fried foods and greasy savouries that lead obesity and associated medical problems, such as high blood pressure, diabetes etc. “A normal diet includes vegetables, fish, olive oil, whole grain meals found in Mediterranean, Indian traditional cuisines, and less oily East Asian diets,” said Gupta.
The study used purified synthetic diets, with the main differences being higher amounts of sugar, sucrose, cholesterol and butter in the western diet compared to control diet. “The control diet contained more of starch and soybean oil, which could reflect more of whole wheat breads like chappatis, rice and vegetables, which are important components of Indian cuisine, with some limitations such as use of turmeric, which is beneficial,” said Gupta.
Intermittent fasting was also found to be beneficial. “The mice were given 60% of the food amount of the sex-and-age matched control mice, but studies with lower restriction of calories (20-30%) have been shown to bring health benefits. The idea is that you should control calorie intake by eating a balanced diet,” said Gupta.
Several studies have shown that time-restricted fasting, where you eat within an eight-10 hours window, leads to weight loss without changes in food or activity levels and protects against metabolic disorders such as diabetes, obesity, fatty liver and high cholesterol, among others.
Most people eat frequently and erratically in their waking hours, wrecking the balance between nutrient and the body’s cellular stress response. People in India on average eat for 15.53 hours in a 24-hour day, found a Delhi University study that tracked what and when people ate using a simple camera phone in 2017. It found that the median breakfast time in India is 6:58 am (between 6:10 am and 7:27 am) and the last meal of the day, which includes snacks, is at 10:45 pm (10:18 pm± 11:58 pm), according to study published in the journal PLOS One. Eating over an extended period does not give the metabolic system time to rejuvenate.
Carbohydrates, particularly sugars and refined grains like white bread, maida and polished rice, are quickly broken down into glucose for the cells use for energy, with the hormone insulin storing the excess carbs as fat in the fat cells. “When you fast for a sustained time, fatty acids are converted into ketones, which are burned for energy and lead to weight loss. Only healthy people, however, must attempt prolonged fasting, as ketosis can be potentially life-threatening in people with uncontrolled diabetes and other chronic conditions,” said Parmit Kaur, chief dietician, All India Institute of Medical Sciences (AIIMS).
The study in Germany identified a single gene, Tnxb, which could be a potential new player in DNA-diet interaction. “The finding will help identify pharmaceutical interventions that benefit a defined subgroup of the population carrying a specific corrupt DNA. The results in the autoimmune-prone mice indicate that dietary regulation of the microbiome (bacteria in the gut) is associated with disease development, which suggests that dietary interventions and/or use of probiotics may be used as preventive measures in populations at risk,” said Gupta.