June 1, 2015

Every so often, science disproves the thinking behind a deeply embedded habit we have. The latest: drinking coffee in the morning.

It turns out, the morning is actually one of the worst times of the day to drink coffee, according to YouTube science channel ASAP Science. The reason? The high levels of cortisol in our bodies early in the morning.

You see, consuming caffeine when cortisol levels are high creates two problems. One is that caffeine interferes with the body’s production of cortisol, a hormone that’s released in response to stress and low blood glucose. The body ends up producing less cortisol, and relying more on caffeine to compensate.

The other effect of drinking coffee in the morning is well-known to habitual morning drinkers: It increases the person’s tolerance to caffeine because it replaces the natural cortisol-induced boost instead of adding to it.

Bear in mind that cortisol levels are high at three times of the day, not just early in the morning, according to a 2009 study. So the best times to drink coffee — or caffeine in general — is between 10 a.m. and noon, and between 2 p.m. and 5 p.m.

Early morning coffee drinkers should consider adjusting their schedule to better optimize their caffeine intake. As pleasant as a cup o’ joe may be first thing in the morning, turns out it’s quite ineffective.

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QUIZ: Should You Eat This or That?

Which is better for you: Half cup of ice cream or 3 scoops of sorbet?

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<strong><b>Answer: A half cup of ice cream</b></strong>
If you eat what you’re craving, you’re more likely to feel satisfied and eat less. And scoop for scoop sorbet contains twice the sugar with none of the filling dairy protein and fat.

Answer: A half cup of ice cream If you eat what you’re craving, you’re more likely to feel satisfied and eat less. And scoop for scoop sorbet contains twice the sugar with none of the filling dairy protein and fat.

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Which is better for you: Real butter or spray on fake butter?

Getty Images; Tara Johnson for TIME

<strong><b>Answer: Butter</b></strong>
Serving size for spray butters (even low-calorie ones) are around a 1/3 second spray. What on earth does that mean? You're better off using a small amount of real butter as opposed to guessing how much you're using of the mystery melange of up to 20 ingredients.

Answer: Butter Serving size for spray butters (even low-calorie ones) are around a 1/3 second spray. What on earth does that mean? You're better off using a small amount of real butter as opposed to guessing how much you're using of the mystery melange of up to 20 ingredients.

Getty Images (1); Gif by Mia Tramz for TIME

Which is better for you: A turkey burger or a sirloin burger?

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<strong><b>Answer: Sirloin burger</b></strong>
Restaurant turkey burgers are often made with dark meat and the skin, so they’re not necessarily better for you (and for the record, they aren't low-fat). You can get a sirloin burger that’s 95% lean meat and gives you 20 g of protein. Just be careful with the toppings.

Answer: Sirloin burger Restaurant turkey burgers are often made with dark meat and the skin, so they’re not necessarily better for you (and for the record, they aren't low-fat). You can get a sirloin burger that’s 95% lean meat and gives you 20 g of protein. Just be careful with the toppings.

Getty Images (1); Gif by Mia Tramz for TIME

Which is better for you: Almonds or pretzels?

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<strong><b>Answer: Almonds</b></strong>
Almonds are high in protein, fiber and fat and will keep you feeling fuller longer. Give high-sodium pretzels about an hour and you'll feel hungry again thanks to the high-carb no-fat or protein content.

Answer: Almonds Almonds are high in protein, fiber and fat and will keep you feeling fuller longer. Give high-sodium pretzels about an hour and you'll feel hungry again thanks to the high-carb no-fat or protein content.

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Which is better for you: Special K or eggs?

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<strong><b>Answer: Eggs</b></strong>
In the morning, you want a meal that will fill you up. Eggs offer protein and fat for satiety, but Special K cereal really only offers carbs and, well, air. If you want carbs to kick off the day, you're better off pairing eggs with a slice of 100% whole grain toast.

Answer: Eggs In the morning, you want a meal that will fill you up. Eggs offer protein and fat for satiety, but Special K cereal really only offers carbs and, well, air. If you want carbs to kick off the day, you're better off pairing eggs with a slice of 100% whole grain toast.

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Which is better for you: Fat free salad dressing or regular salad dressing?

Tara Johnson for TIME

Answer: Regular salad dressingTo absorb fat soluble vitamins like Vitamins E and K in vegetables you need to consume them with a fat to aid nutrient absorption. Fat-free dressing, meanwhile, is low-calorie but gets its flavor from added sugar and salt.

Tara Johnson for TIME (5); Gif by Mia Tramz for TIME

Which is better for you: A low fat cookie or dark chocolate?

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Answer: Dark chocolate “People believe fat free is calorie free,” says Keri Gans, a registered dietitian in New York City. “Go for the real thing.” Fat free cookies tend to be high in carbs, sugar and fake sugar. Try a nice piece of antioxidant-rich dark chocolate instead.

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Which is better for you: Low fat Greek yogurt or 100 calorie Yoplait yogurt?

Tara Johnson for TIME

Answer: 2% Greek YogurtA little fat is good in the morning to keep you full—plus it has upwards of 17g of protein per container. Fat-free "fruit" yogurt is high in sugar—7 to 10 g per serving—and lower in protein.

Tara Johnson for TIME (2); Gif by Mia Tramz for TIME