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AS ANYONE WHO has ever daydreamed about their post-workout meal during a long run or tough lifting session knows, meals can be motivating.
But then there are other days when you don't feel hungry at all—even after a workout. Does a lack of appetite signal that something else is up with your body? Or is it completely normal?
Hunger actually depends on a whole host of internal and external factors—and temporary loss of appetite is harmless. Maybe you just had a busy morning and you forgot to eat lunch until, um, 2:00 p.m. Or maybe you had a huge lunch and sitting down to another full meal doesn’t sound all that exciting. These types of brain-belly disconnections are common.
But then there’ the opposite end of the concern spectrum.
Regular loss of appetite could signal that you may have a medical condition, says Kacie Vavrek, R.D., at Ohio State University.
"Some of the main reasons [for appetite loss] are going to be more disease-related, like a cold or some GI issues," Vavrek says.
That said, certain medications can also cause loss of appetite. So, just to be safe, read up on these six reasons for appetite loss—and then determine if you can relate to any of them so much that it might be time to take yourself to the doctor.
And if everything seems a-okay, well, here’s to your next meal.
Can the common cold or infections cause hunger loss?
Yes. (As if being sick isn't bad enough.)
Losing your appetite is common if you have a cold. This is why you sometimes lose weight when you're sick—you simply just don't want to eat. Your white blood cells release cytokines that help fight off infection, but these chemicals can also cause a loss of appetite.
Bacterial infections like pneumonia and strep can also lead to a dip in hunger. Of course, this subsides once you recover.
Can stress and anxiety cause hunger loss?
You often hear about people who "stress eat" their feelings, but sometimes anxiety can make you lose your appetite too.
One reason is that stress causes your body to release a hormone called epinephrine, also dubbed adrenaline, which temporarily diminishes hunger, according to Harvard Health. However, this loss of appetite is usually short-lived. Persistent stress can cause your body to release cortisol, a hormone that revs up appetite.
Can medications cause hunger loss?
It's no secret that medications come with a long list of potential side effects. Gastrointestinal issues, like nausea, stomach pain, or diarrhea, are commonly found on prescription warning labels.
And it goes without saying that these side effects can make you lose your appetite. Narcotics like codeine and morphine—as well as some antibiotics—are common appetite killers.
Can the weather affect hunger?
There's a reason most people crave lighter foods like salad and fresh fruit in the summer. In fact, some people may feel like skipping meals completely when the temperatures rise, according to Vavrek.
"Hot environments can suppress your appetite where cold environments can increase your appetite," she says.
Your body produces heat when eating. If temperatures are unbearably warm, you'll feel less inclined to dig into a meal and raise your own internal temperature, Vavrek explains.
Can mealtime intake cause hunger loss?
Oh, totally.
In fact, if you're eating the right amount of two key nutrients at every meal, you may not even get that hungry between meals. Those key nutrients? Protein and fiber.
Experts agree that eating at least 30 grams of protein and 10 grams of fiber at each meal will both help you fill up and not overeat during a meal and keep you feeling full until the next—whenever that may be.
If I never feel hungry, is that a bad sign?
Sometimes, lack of appetite may signal other medical issues including hypothyroidism, diabetes, or even cancer. Each will likely be present with other symptoms, but signs can be subtle. It's important to see your doctor if food is always unappealing.
According to Vavrek, you should head to the doctor if you've lost weight or gone three to four days without an appetite. It's important to determine whether an underlying medical condition is at the root of the problem.
You'll also want to remedy the problem quickly because your body will use protein stores as energy, causing you to lose muscle mass.
"It’s very easy to lose muscle and hard to get it back," she says.
