WASHINGTON — My grandfather, Murray Fox, 84, had been hospitalized after three months of complete exhaustion for which there was no obvious cause. Just rising from the couch in his small Rockville, Md., apartment had become a draining endeavor. Walking 10 feet to the microwave left him too tired to zap something once he got there. His appetite had vanished along with his energy. First he lost five pounds. Then 10, then 20, until he wasted to a diminutive 120. He thought he was dying.

After a few days, though, his doctors — along with my WebMD-savvy parents — figured out that he probably had Addison’s disease, a disorder that occurs when a person’s adrenal glands fail to produce enough of the steroid hormone cortisol.

The cure came in the form of a few small hydrocortisone pills. As my grandfather tells it, “I took them on a Sunday, and by Monday I was better. It was like a movie.” As his discharge approached, a doctor told him that at his age, it was particularly important to get back up to fighting weight. My grandfather protested, saying he had no appetite. “How can I eat?” he asked.

“Figure out what you like, and eat it,” the doctor replied.

Decreased appetite is a common problem among the elderly. It can be traced to anything from cancer to tooth decay, or in my grandfather’s case, a hormonal imbalance. The Mayo Clinic offers several remedies, among them spicing up bland food, getting more exercise and planning snack breaks between meals.

But I found a more compelling route in David Sutton’s 2001 book “Remembrance of Repasts: An Anthropology of Food and Memory.” The people he studied for 18 years on the Greek island of Kalymnos urged him to “eat in order to remember,” because the rituals of eating formed a significant part of their cultural identity. Maybe my grandfather could learn something from the Kalymnians, I thought. Maybe I could cultivate his appetite by reminding him of meals he had enjoyed in the past.

Memory lane

My grandfather has always been an avid eater, though admittedly no gourmand: He’s a man who scarfs, not savors. But his stories nearly always involve some neighborhood Italian joint, some late night passed in a Greek diner, some restaurant in the backdrop. Tangential to the story, but important.

The son of Eastern European immigrants, he kept strictly kosher until he was about 13, when his grandmother, a religious woman, died. His parents were nearly always busy at their store in Brooklyn. So his older sister, Anna, took over the household, and she couldn’t have cared less about keeping kosher.

“Everything was screwed up,” my grandfather said with a laugh. From then on, he was free to explore as far as the Lower East Side of Manhattan, which was checkered with dingy Chinese joints. That was where he probably had his first taste of treif, or unkosher food.

Over the years, Americanized Chinese food became a constant in his life. After he and my grandmother opened their own store in Queens, they’d often stop for dinner at the Chinese restaurant across the street. He’d order shrimp with lobster sauce.

“Your grandmother was kosher,” my grandfather explained mischievously. “So, I got her to eat clams and oysters.” She took to them like a fish to water, and in Chinese restaurants. Juicy dumplings swathed in sweet dough, chow mein, vast pu pu platters. “She’d order the whole menu,” he recalled. After her death in 1993, he would order several days’ worth of Chinese food delivered to his Queens apartment until he learned to cook for himself.

Chow fun

Although my grandfather’s appetite made a modest comeback when the medication first kicked in, he still couldn’t manage large meals, and meaningful weight gain remained elusive. Part of that, he maintained, was just getting older.

He had a joke for it: An elderly man and woman are sitting in a cafe. They order one small sandwich between them. A waitress takes notice and sighs, “How sad! They’re so poor they can only afford a single sandwich.” She offers generously to buy the couple a second meal, so both could eat. “Oh, it’s not that we’re too poor to buy two,” replies the wife. “It’s just that he’s using the teeth!”

I figured that if anything could draw a big appetite out of my grandfather, it was Chinese food. My family had moved him to Maryland in 2004 to be near us, so I took us to Ming’s, a restaurant in Washington’s Chinatown. He’d never been, but the place has a homey quality I hoped would remind him of the places he used to frequent in New York.

We ordered a bevy of old favorites — beef chow fun, pork dumplings, crunchy spring rolls and, of course, shrimp with lobster sauce. He began recounting meals past, a few at first and more as the meal progressed. Soon he recalled the family that ran the Chinese restaurant across from the store, and the time my mother dated the owner’s son.

“How’d the date go?” I asked him. He laughed. The romance didn’t last long, he told me. The boy’s clothes smelled of the restaurant’s food.

But beyond the stories, it was his appetite that was striking: He finished on his own three-quarters of the shrimp and lobster sauce, his old go-to, taking care to have the rest wrapped up for his dinner that night.

Corned Beef Row

However much he loved Chinese, though, delis and diners were the source of everyday sustenance. As a teenager, my grandfather and his older brother explored the neighborhood restaurants, ordering triple-decker sandwiches stacked high with lunch meats, and slices of corned beef tucked between thick slabs of mustard-smeared rye.

So our quest for high-calorie food had to take us in that direction. I decided our best bet for traditional Jewish deli was Attman’s, one of the last remaining relics of Baltimore’s famed Corned Beef Row.

Driving over, I asked him to describe why he liked corned beef. Was it the saltiness? How tender and fatty it can be? How it combines so perfectly with mustard and rye? He looked at me, confused. “It tastes good!” he said, a bit exasperated. When we arrived, he noshed with the gusto of a much younger man, on corned beef, pastrami, tongue, knishes and hot dogs with sauerkraut.

There, heady from meat and the Jewishness of it all, he was reminded of an old joke. He had a difficult time remembering it, so my mother, who’d tagged along, filled in the gaps.

It goes like this: A woman goes to a butcher, and she says to him, “Give me a good one!” The butcher brings out a chicken, and the woman takes a whiff. She tosses it back and says, “No! I want a good one!” It continues back and forth like this for some time until the butcher has had enough.

My grandfather was reeled back into the memory just in time to steal the punch line. “Lady!” he shouted, in character. “’You think you could pass such a test?!’”

Hungry like a horse

After Attman’s, we ambled over to Vaccaro’s Italian Pastries, well known for its cannolis overflowing with ricotta. I managed only half of mine; my grandfather finished all of his. That night, we ate dinner at a local deli, where he ordered triple deckers with bacon and nearly cleared his plate.

His appetite seemed fully returned. Had it? I asked. “Like a horse,” he replied.

In the last two months, my grandfather has packed on about half the pounds he’d lost. I reminded him of the other time in his life he’d gained a significant amount of weight.

After enlisting in the Navy at age 17, he became enamored with canteen food and went from 120 pounds to 150 in a matter of months. The mess hall’s chipped beef, he said, had a lot to do with that.

When I suggested we track down a plate of it, he recoiled. “I hate chipped beef!” he cried. I was confused; hadn’t he just told me otherwise? “That was 60 years ago!” he said, laughing. I understood. Tastes change, but sometimes the story is too good to stop telling. A person, it turns out, can have an appetite for things beyond food.