You are what you eat. The age-old aphorism has received a 21st-century genetic nod of approval, with an added caveat: when. A new study shows time-restricted eating (TRE), where food consumption is limited to a window of eight to 10 hours, regulates the nervous system and improves cognitive function and metabolic activity. Even though the study was conducted on mice, it expands the scope of nutrition epigenetics that looks at the connection between food and gene expressions, and how certain foods can activate specific genes.
Genes of good health Conducted by researchers at the Salk Institute for Biological Research, US, the study, published in Cell Metabolism in January this year, found that TRE activated genes in over 22 regions of the body and brain. Almost 40 percent of the genes in the adrenal gland, hypothalamus and pancreas showed a shift, reiterating the positive effect of nutritional interventions in improving brain, heart, lungs, liver and gut health.
“TRE lowers cholesterol and blood sugar, minimises cellular dysfunction, improves the production of the gut microbiome and builds immunity,” says Dr Atul Bhasin, Director, Internal Medicine, BLK-Max Super Speciality Hospital. The therapeutic protocol also improves metabolism and aids weight loss, which is important as obesity presents as a risk factor in cancer development, according to a study published in August 2022 in the journal Cancer and Metastasis Reviews.
Meal timings matter TRE follows a self-selected eight-to-10-hour window, but the most effective is the 7 am-3 pm period, according to a report published in the journal JAMA Internal Medicine in August 2022. “Starting early has several advantages, which are modulated by the circadian rhythm that carries out essential functions. One of them is homeostasis, which maintains insulin levels and breaks down food.
This is most active in the morning, which is why an early TRE pattern improves metabolic health markers,” says Bhasin. Delhi-based data analyst Soumya Khaitan is testimony to the life-changing benefits of an early TRE plan. Her 10-hour work shift in a new company had her glued to the seat.
Coupled with erratic eating habits, the kilos piled. She went from 54 kg to 68 kg in three months, and began experiencing knots in her spine. With no time (and intention, she confesses) to work out, Khaitan tried a few diets her friends suggested; neither lasted beyond a few days. As the muscle spasms worsened, she saw a doctor. The diagnosis: paraspinal muscle atrophy with a herniation in the L-5 disc.
What followed were ultrasound and physiotherapy, but since Khaitan’s weight added to the condition, she was referred to a nutritionist who put her on an early TRE diet programme for six weeks. By the end of it, she lost about 8 kg. Moderate exercises were gradually introduced back into her routine. Despite being fit, she has stuck to the nutritional intervention. “Restricting my per-day caloric intake facilitated what my doctors explained as metabolic switching. It’s when the body runs out of sugar reserves and starts burning fat during fasting periods, aiding weight loss. To my surprise, TRE helped fix my menstrual cycles too, and reduced acne and hirsutism, which I had suffered from for many years due to PCOD,” she says.
At the heart of it “Whether self-timed or an early plan, the biggest way in which TRE helps is by disrupting random eating schedules that can lead to blood pressure irregularities, obesity and type 2 diabetes,” says Bhasin. On the other hand, it may decrease LDL cholesterol, enhance the body’s response to insulin, and improve the markers that cause heart attacks, he adds.
The other side of the coin TRE may have some adverse effects, especially in the initial phase of the diet. Here are a few along with ways to tide over them. Tiredness: One of the common side-effects of TRE is lethargy caused by a dip in blood sugar. “To combat it, drink more water during your fasting period. During the feeding window, include high sources of electrolytes such as spinach and collard greens, nuts, milk and coconut water. Take short naps and exercise for at least 20 minutes during the day,” says Dr Priyanka Rohatgi, chief nutritionist at Apollo Hospitals.
Feeling hangry: Hunger and anger are controlled by common genes, that’s why a drop in glucose can make one irritable and angry. “Gradually extend the fasting window. For instance, let the cut-off time be 7 pm in the first week, 6pm in the second week, 5pm in the third... until you reach the ideal cut-off of 3 pm,” says Rohatgi.
Cravings: Because of the long fasting period, the hormone leptin released from the adipose tissue starts to drop, causing cravings, especially for sugar. A nutritionally-rich diet with fewer carbohydrates and more fat will help promote satiety.
Sleep trouble: Fasting leads to a dip in the sleep hormone melatonin, which can interfere with shut eye. “Relaxation routines such as meditation, a warm bath, or soaking feet in warm water with Epsom salt can promote restfulness. You can also massage sleep-inducing points such as the spirit gate at the edge of your palm, below the little finger; and the inside of your lower leg, about three-four inches above the ankle,” says Gurugram-based mindfulness coach Kinjal Parekh.
DO IT RIGHT ● Choose a longer caloric window and gradually reduce it ● Do not skip breakfast; try to have a high-protein one ● Restrict caffeine intake to morning hours ● Avoid extreme workouts during the initial weeks of TRE ● People with diabetes, an active heart disease, pregnant women or those breastfeeding, should consult their doctor before starting a TRE diet
