Ayurveda, the traditional medicine of India, believes that eating according to the seasons is important for maintaining good health.  This shift in diet helps to compensate for the particular qualities of that season.  The seasonal emphasis for fall is to balance the cool, dry, light qualities of the season with warm, moist, well-spiced dishes.
Foods to favor include root vegetables, such as sweet potatoes, carrots, turnips, parsnips, beets and winter squashes, cooked greens such as collards, kale and swiss chard, warming spices such as ginger, cumin, fennel and salt, raw or roasted nuts and seeds, moist grains cooked with extra liquid and sweet fruits.  Proteins should come from small legumes like lentils and split peas, tofu, eggs and meat.
Use the following Fall Spice Mix to aid the digestion in shifting to cooler weather.  It will encourage strong digestive fire and stimulate and soothe the digestive organs.

Fall Spice Mix
Makes 1/4 cup

1 Tbsp. coriander seeds
1 Tbsp. cumin seeds
2 tsp. fennel seeds
1 Tbsp. turmeric powder
2 tsp. ginger powder

Dry roast the coriander, cumin and fennel seeds in a heavy-bottomed pain on medium-low heat until you can smell the spices.  Transfer the seeds from the pan into a wide bowl and cool completely.  Grind the whole roasted seeds to a uniform consistency in a coffee grinder or mortar and pestle.  Pour them back into the bowl and stir in turmeric and ginger powders.  Store in a small jar with an airtight lid.  Use in any dish!
From The Everyday Ayurveda Cookbook by Kate O’Donnell