I've heard it often said and experienced it myself on various continents (including Asia): you enjoy a terrific Chinese, or Thai, or Malay dinner, only to feel hungry again a short while later. Is this our imagination playing a trick on us appreciators of Chinese cuisine? Or is it a western counterpart to the fact that many Asians don't tolerate milk? — Erwin Kuhn, Germany
We had a helluva time with this one, Erwin. The problem wasn't just coming up with an answer. It was figuring out the question, which we've gotten in different forms over the years. Possibilities:
1. Why, after eating Chinese food, do you soon feel hungry again?
2. Do you, in fact, after eating Chinese food, soon feel hungry again?
3. People used to say that after eating Chinese food one soon feels hungry again. Now they don't. What changed?
All we were able to establish initially was that, long ago (at least), people did in fact say the Saying, as I'll refer to it, and that this wasn't some mass hallucination. My assistant Una found the following fragment from a dramatic piece published in the literary magazine Golden Book in 1934:
julie (in a flat tone): Yes, but the trouble with that Chinese food is, no matter how much you eat you feel hungry an hour later. Have you ever noticed that?
ham (the Orientalist): It's the rice.
The easily satisfied will say, "So there you have it — it's the rice," and move on. Those of subtler bent will inquire more closely. This Julie — why is she speaking in a flat tone? Has she been drugged? Has Ham, the glib Orientalist, put something in her lo mein? I have no idea, and if we waste any more time on such flighty inquiries we'll soon run out of column. However, having eaten considerable quantities of the impugned starch without subsequently experiencing premature hungriness, I feel confident in saying: it's not just the rice.
What, then, is it? I'm working on that. Some preliminary observations:
• I don't personally feel hungry soon after eating Chinese food, nor do I hear the Saying much these days. I therefore incline to the view that while the Saying may have been true years ago, it's not true now.
• Different foods are digested at different rates. One measure of digestion speed is the glycemic index (GI), which measures how quickly and how high your blood sugar levels rise after eating. This has led some to wonder if there's a connection between GI and subjective feelings of satiety, or fullness, after a meal. Answer: no. The GI correlates with satiety for some foods but not others, and correlation varies depending on how the food was processed and the fat and protein levels of the meal overall.
• Taking a different tack, other researchers (Holt et al, 1995) have developed a satiety index, or SI. Testing satiety typically involves eating a specified calorie amount of various foods and rating how you feel over the next two hours on a scale from "extremely hungry" to "extremely full." The ratings are then converted to a numerical score by comparing them to ratings for white bread, whose SI score is fixed at 100. From this we learn that two major components of Chinese cuisine — white rice and white pasta noodles — have much lower SI values (138 and 119 respectively) than the starch that was once a mainstay of American food (I won't call it cuisine), namely the potato. The humble tuber has an SI of 323, by far the highest of any food tested.
Here we glimpse an explanation. I can't speak to German dining trends, but prior to 1980 or so, potatoes in various forms (mostly mashed, but also baked, fried, scalloped, au gratin, and so on) were a standard feature of the American dinner menu. Since then, in my casual observation, they've become less prevalent, and potato stats bear this out.
So when people said the Saying 50 years ago, they may simply have been comparing Chinese food to the meat-and-potatoes fare to which they were accustomed. In other words, it's not that Chinese food left you feeling hungry after an hour, but that the standard American diet left you feeling exceptionally full. As American cooking became less potato-dependent, the difference in satiety potential between Chinese and U.S. food likely diminished.
Other factors may also have been at work. For example, eating a salad before the main course — common in Western-style restaurants but less so at Chinese places — increases a diner's feeling of fullness, whereas high-fat soups, like the old-school egg drop and hot-and-sour varieties, have only minimal impact on satiety. Another element in the decline of the Saying may be the increased popularity of spicy Hunan and Szechuan cuisine compared to the bland Cantonese that once dominated Chinese menus — the capsaicin in hot peppers is known to reduce hunger.
We haven't yet tested any of the above — after last week's adventure with alcoholic cupcakes, Una and Fierra are on a diet. For now, however, I don't blame the rice; I blame the spuds.
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