I’m sure you’ve heard the song, “9 to 5.” It has catchy lyrics, but they don’t describe the real-life experience of about 15 million Americans. That’s how many shift workers—on duty evenings, nights, or in some rotating or otherwise irregular schedule—the U.S. Bureau of Labor Statistics estimates are in the workforce. And you may be one of them.

Occupations affected include: the military, food services, transportation, manufacturing, and industry, police, firefighters and security personnel, and health-care providers.

Unlike nocturnal animals such as owls and mice, most humans have some trouble adjusting to this strange lifestyle of working at night and sleeping in the day. This is because shift work, including night work, disrupts the body’s “circadian rhythm” – the internal clock that governs eating, sleeping, body temperature and other regular biological processes, all hardwired and regulated to the rising and setting of the sun.

As it turns out, messing around with that clock can have some serious consequences on your weight. Shift workers have a higher prevalence of being overweight—a fact substantiated by research. There are four main reasons why.

Exercise After Shift Work

First, regular eating and exercise habits are tough to maintain on shift work. You can get bored easily, so you tend to nibble on junk food  in response. According to a study by the New York Obesity Research Center and published in Nutrition in 2000, late-shift workers gained an average of 9.5 pounds during their late-shift tenure, while their day-shift counterparts gained only 2 pounds.

Night Shift Work: The Effects on Your Metabolism

Second, there’s a hormonal issue. When you sleep and eat at irregular times, your metabolism gets thrown out of whack. At night, during sleep, your body’s insulin-making processes naturally go into hibernation. You’re not eating, so the body doesn’t require much insulin action so your body drives nutrients toward fat accumulation this late in the day.

Digestive Problems Avoid Gaining Weight

Third, digestive problems are at fault. Shift workers have two to three times as many digestive problems as their peers on the day shift. During nighttime, your digestive system shuts down and doesn’t secrete the normal enzymes. Plus, your metabolism slows down in the evening. Many shift workers report diarrhea or constipation, gastric and peptic ulcers, gastritis, nausea and weight gain.

Sleep Problems

Finally, there are sleep problems. Shift workers are among the most sleep-deprived segments of our population. It’s tough to sleep soundly during the day, when your body clock is screaming for you to be up and at it. Also, sleep deprivation drives down leptin, a hormone produced in fat cells that tells your brain when you’re full. At the same time, your substandard snoozing causes a rise in ghrelin, a hormone that makes you feel like you haven’t eaten since two Mondays ago.  Numerous studies showed that those who sleep less than eight hours a night have lower levels of leptin, higher levels of ghrelin and more body fat than the long-slumbering subjects. Chronic sleep deprivation can thus drastically increase your risk of gaining weight.

Avoid Junk Food

One of the things you can do to improve your energy and overall health is to eat a healthy diet, rich in vitamins and minerals. Those chocolate bars and packets of crisps in the vending machines at work may be tempting, but they’re probably doing you more harm than good, reducing your energy levels and stamina even further. Donuts and cakes may give you an instant “buzz,” but the downside is that you’ll crash, and large amounts of refined sugar can lead to extreme mood swings.

The same goes for drinks. Cut down on the cans of coke and other fizzy drinks (even the “diet” variety) and avoid beverages with caffeine because you’ll find it harder to sleep when you get home. Instead, go for water. It’s important to keep hydrated, since dehydration can lead to headaches and fatigue.

On night shift, eat small light meals, with lots of raw salads, fruit and veggies. These will give you energy but won’t make you sleepy.

Sometimes shifts are long, so if you take sandwiches, make them whole grain bread. Try gluten-free bread. The older you get, the more difficult gluten is to digest and it can block the bowel. A healthy bowel that is moving will give you more energy.

If you really want to lose weight and shed pounds, take the time to learn more about my 17 Day Diet Meal Plan. You’ll learn how to start eating healthy to lose weight safely while dining out as well as create a regular meal plan.

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