Why eating late at night will do more than just make you gain weight – it also raises risk of diabetes and heart disease, study reveals

• Eating later increases glucose and insulin levels, which is linked to diabetes.
• It also raises cholesterol and triglycerides, which damage your heart health.
• Daytime eating produces hormone changes to helps you feel full longer.
• “Eating earlier may help prevent detrimental chronic health effects,” says expert.

There is a well-known link between eating late and weight gain – now new findings suggest it also increases your risk of diabetes and heart disease.

A team of US researchers found eating later raises boosts glucose and insulin levels, which are implicated in diabetes. Late-night meals also raise cholesterol and triglycerides, a type of fat in your blood, both which can increase your risk of heart disease.

And in line with previous studies, the research discovered late-night meals caused people to gain weight by reducing the body’s ability to burn fat. The findings emerged from a study by the Perelman School of Medicine at the University of Pennsylvania, further confirms that eating late at night has a host of negative health effects.

‘We know from our sleep loss studies that when you’re sleep deprived, it negatively affects weight and metabolism in part due to late-night eating, but now these early findings, which control for sleep, give a more comprehensive picture of the benefits of eating earlier in the day,’ said lead author and research associate professor of psychology Namni Goel.

How they conducted the research

The researchers set out to study the metabolic consequences of consistent delayed eating compared to daytime eating. They instructed nine adults of healthy weights to spend eight weeks to eat during the daytime, which involved consuming three meals and two snacks between 8am and 7pm. Then the group followed a delayed eating routine – having three meals and two snacks eating from noon to 11 pm, for eight weeks.

There was a two-week break in between to make sure there was no “carry overˮ effect. Their sleep patterns were kept consistent – between 11 pm to 9 am – in both phases to eliminate any effect from lack of sleep, which is linked to obesity. At key points across the study, the researchers measured changes in weight, metabolism and energy used, and they made sure the two-week break allowed all measures to return to baseline before the next phase was begun.

Key findings

Late eaters have higher body mass indexes. Research has consistently shown that people who eat late at night weigh more than those who eat all of their food earlier in the day.

According to a 2013 study published in the International Journal of Obesity, early eaters lost approximately 12 percent of their body weight, while late eaters lost only 8 percent, even though they all followed the same diet and exercise regime. The late eaters were also found to have consumed fewer calories during breakfast and were also more likely to skip breakfast altogether – practices experts say encourages weight gain.

And according to a 2007 study published in the same journal, people who eat most of their food at night have higher body mass indexes than people who eat earlier in the day.

Another study published in The American Journal of Clinical Nutrition, showed that participants who ate between 11 pm. and 5 am gained more weight than those who did not eat during those hours. The research discovered that when participants ate later, compared to when they ate during the daytime, their weight increased. They found late-night meals caused people to gain weight by reducing their body’s fat metabolism – the process by which fats are broken down and used for energy.

Tests revealed that eating later led the participants to metabolize fewer lipids or fats. It was also found that delayed eating led them to store carbohydrates – which can lead to weight gain and raised blood sugar and insulin levels. And indeed insulin and fasting glucose were found to be higher when people ate later, and their cholesterol and triglyceride levels rose too.

Eating earlier in the day was found to produce hormone changes that helps you feel full longer and therefore not overeat. For daytime eaters, the hormone ghrelin, which stimulates appetite, peaked earlier in the daytime.
Meanwhile, leptin, which keeps you satiated, peaked later, suggesting that the participants received cues to eat earlier, and eating earlier most likely helped them to feel full longer.

This suggests that eating earlier may help prevent overeating in the evening and at night, say the researchers.

What the experts say

Previous studies have suggested similar results, but this is the first long-term study – albeit a small one – that has analyzed the health effects of the timing of eating patterns that also controlled for sleep-wake cycles, exercise and macronutrient intake.

Professor Kelly Allison, senior author on the study, said: “While lifestyle change is never easy, these findings suggest that eating earlier in the day may be worth the effort to help prevent these detrimental chronic health effectsˮ.

“We have an extensive knowledge of how overeating affects health and body weight, but now we have a better understanding of how our body processes foods at different times of day over a long period of timeˮ.

yogaesoteric
November 28, 2018

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