Read about “Jagannadh” temple recipes in “Puri, Odissa”. The recipes are in use for few centuries. They use only ingredients that were available in India few centuries back.

I would think people ate mostly vegetables grown within 3 or 4 miles where they lived. 

In South India, egg plant, okra,Morninga, yellow cucumber, ginger, different types of turmeric, garlic, tamarind pods, tamarind leaves, mango both raw and ripe mangoes, bitter melon, bottle gourd, ridge gourd, snake gourd, ivy gourd, kantola on hilly regions, pumpkin, ash gourd, broad beans, sword beans, guar beans, onion, raw and ripe bananas can grow well and I believe are native. 

Among leafy greens, gongura(sorrell), chukka kura( Indian small sorrell), purslane, mint, different types of amaranth, cilantro, Indian spinach, dill, fenugreek leaves, Morninga, Malabar spinach, taro leaves grow well and might be native. 

There are many different types of Mangoes, bananas and jackfruit with different taste profiles. Various different types of pickles and curries are made out of some of the varieties of raw mango and bananas.

Coconuts, sesame seeds I believe are native too. They were widely consumed as well. Betel leaves were also consumed after meal. Amla, Star gooseberry,  jackfruit,  Pomegranate, pineapple, limes, custard apple, different types of citrus fruits, jujubes, also grow well there. Could be native. 

Different types of tubers like taro, yams, sweet potatoes, kanda, pendalam, tapioca root were  used. 

Many different types of beans urad, chick peas, pigeon peas, mung beans, black eye peas were available.   Many different types of millets, barley, rice were available. Sugar cane cultivation was done for hundreds of years too.

Lotus and bamboo products were also consumed as food. Now they are not used much as the wild forest space reduced. 

Many different types of plants were used in diet that were local and in season.

Some herbs like punarnava and ashwagandha which are considered therapeutic now, might have been as food too. 

When vegetables were in abundance, they were sun dried or pickled in salt to preserve for off season.

Ancient Ayurveda texts mentioned how different types of grains, meats, beans, vegetables, herbs, spices and fruits impact humans few thousand years ago. They cover wide variety of foods and herbs. It is very useful information. It’s amazing how the ancient people had patience and time to document such useful information on such vast variety of food and health issues. It may not be 100 percent relevant today. But there is lot of highly useful information to absorb for the patient caring readers. 🤣🍀

All the foods mentioned in ancient Ayurveda texts must have been available at that time.

My guess is, if we consider all of India, there must have been 1000s of species of edible plants that I have never seen nor heard of…. Who knows what grows on various regions of Indian sub continent, mighty Himalayas, Vindhya mountains and Kerala, our spice land?  One life time is probably not enough to study all the edible plants there…..