Late night snacking could lead to holding onto postpartum weight longer

Led by researchers from KK Women’s and Children’s Hospital (KKH), the new study looked at 687 pregnant women and asked them to self-report their eating times and diet quality at weeks 26 to 28 of pregnancy.

The researchers also calculated the women’s maternal weight in the first trimester of pregnancy and at 18 months postpartum.

The findings, published in the journal Nutrients, showed that overall, 16 percent of the women gained and retained five kilograms or more at 18 months after giving birth.

Moreover, the women who ate more of their daily food intake after 7pm in the evening, or who ate a lower quality diet, were more than three times more likely to experience postpartum weight retention of five kilograms or more.

“Our research, based on multi-ethnic Asian women, shows that although predominantly night eating and lower diet quality have been independently linked with weight gain, practicing night eating along with low diet quality demonstrated the greatest likelihood of substantial postpartum weight gain and retention even after 18 months,” said lead Author of the study, Dr Loy See Ling.

The findings could have long-term implications for women, with the researchers noting that there is evidence that retaining more weight after the first year of giving birth is associated with a higher body mass index even at 15 years postpartum. In addition, weight retention after having a baby appears to be more harmful to health than weight gain at any other point in life, as body fat is typically deposited in the abdomen, near vital organs, rather than in other parts of the body.

Co-author of the study, Associate Professor Fabian Yap, said that eating at night may be potentially more damaging than eating a lower-quality diet.

“Our body systems have evolved to metabolize food during the day and rest during the night. Hence, consuming more calories at night than day mismatches our body’s natural body time clock by disrupting the metabolic rhythm in various organs such as liver, stomach, pancreas, fat tissue, resulting in disruption of energy metabolism. The consumption of more calories at night is also closely linked with a later bedtime and hence, associated with overweightness and obesity.”

Associate Professor Yap and Dr See Ling recommend that pregnant women follow a healthy diet during pregnancy, one which is rich in whole grains, fruits, vegetables and low-fat dairy products and low in fatty, salty and sugary foods. They also advise eating meals at regular times of the day, changing meal times to earlier in the day or if you do eat later at night, try to eat lighter foods.