There is a famous old Japanese saying about aki nasu or fall eggplants: "Aki nasu yome ni kuwasuna" — "Don't let the daughter-in-law eat fall eggplant."

There are two theories behind what this means. One plays on the age-old and pretty much worldwide conflict between the mother-in-law and daughter-in-law.

In Japan, though it happens less often now, it is traditional for the daughter-in-law to live with her husband's family after marriage. Even with a new "wife" in the house, it would be the mother-in-law who continued to rule the household — and the kitchen would remain her domain. To the young bride, the mother-in-law could be terrifying, and in some households the younger woman would end up in a position that was little better than that of a servant. In this scenario, eggplants, which are particularly good in fall, were considered too much of a delicacy to feed to such a lowly family member.

A little less disparaging is the second theory. Since eggplants are of the nightshade family of vegetables, which are high in water content, they are supposed to have a "yin" or cooling effect on the body according to traditional Chinese medicine. Therefore, they were considered to be detrimental to the health of a young woman in her child-bearing years and particularly harmful to a pregnant woman. No eggplants for the daughter-in-law then; especially in the fall when the weather gets cooler.

Whether to protect the daughter-in-law or deprive her, the eggplant saying reminds us of the changing family dynamic in Japan. Nowadays women rely more on doctors' advice than old-wives tales when it comes to pregnancy, and daughters-in-law are likely to be a whole lot bossier than their in-laws. Many women also flat-out refuse to live with their spouse's family, even though just a generation or two ago it was expected of them (especially if the woman married an eldest son). Fall eggplants, it seems, are no longer taboo for anyone.

Great news, because eggplants are not just tasty, they're good for you too. Besides the traditional belief that eggplants have a cooling effect on the body, which could help combat the lingering heat in early fall, they are rich in vitamins (B6, pantothenic acid, niacin, riboflavin, thiamine, folate and vitamin C), minerals (potassium and manganese) and a good source of fiber.

Nasunin, a phytonutrient anthocyanin that gives the skin of the eggplant its purple color, has also been promoted as an antioxidant said to protect cell membranes from damage. Anthocyanins, in general, have been researched by many scientists, including a 2000 paper from the University of California, Okayama Prefectural University and Yamagata University in Japan on the antioxidant activity of nasunin. Whether nasunin or any other antioxidants really have anti-aging properties might be dubious, but adding eggplant to your diet is surely a good thing; and since standard Japanese varieties are much smaller and slimmer than their Western counterparts, you get a much more of the nutritional skin per serving.

Incidentally, large Western-style eggplants are called bei nasu, or American eggplant, in Japan — even though in the United States they're usually thought of as coming from the Mediterranean. Another type of eggplant that you might see, especially in the Kansai region, is the large round kaga nasu, which has bright purple, thin skin.

Besides eggplant, look for these in-season, typically Japanese foods at your local markets and on restaurant menus in September and October.

Renkon (new-harvest lotus roots): These are tender and crunchy and great when lightly blanched and served in salads or stewed dishes.

Yurine (edible lily bulbs): These are a little like Jerusalem artichokes.

Shin-shoga (new-harvest ginger): Very tender, these are not as strongly flavored as mature ginger roots.

Ginnan (ginko nuts): Peeled and blanched, ginnan are often served in fall dishes.

Kabocha squash: Small, old Japanese varieties of autumn kabocha are generally sweeter than their hybrid Western cousins.

Mushrooms of all kinds are in season in the fall, including the king of mushrooms in Japan, the wildly expensive matsutake.

Kuri (chestnuts): Tasty when boiled and steamed with rice.

Kaki (persimmons): A sure sign of fall, as are the Japanese or Asian pear nashi.

Kyoho grapes: Japanese consumers favor these huge, sweet grapes.

Satsumaimo (sweet potatoes) and satoimo (taro root): These come into season from late October, as soon as the weather turns really cool.

Oily blue-skinned fish, such as mackerel and sardines, are considered to be at their richest and tastiest when the sea waters turn cold.

Sanma (saury) is also synonymous with fall, as the kanji characters for it are "fall, sword, fish."
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