Lentils, chickpeas and beans sit at the centre of Indian cooking and behave unlike other staples once eaten. The reason is that a meaningful part of what they contain is not digestible by human enzymes at all.
Two different things are called fibre
Fibre is a broad label covering plant carbohydrates that human digestive enzymes do not break apart. Pulses contain both the soluble and insoluble kinds in significant quantity.
Soluble fibre dissolves and forms a viscous gel in water, which is why a lentil dish thickens as it cools. Insoluble fibre keeps its structure and passes through largely intact.
Because the two behave differently, foods described identically on a label can act quite differently in practice.
Why the small intestine leaves them alone
Human digestive enzymes are shaped to break specific chemical bonds, and the linkages holding fibre together are not among them. The material moves onward chemically unchanged.
Pulses also carry a family of complex sugars that resist digestion for the same reason. These reach the lower gut still whole.
What happens next is done by gut bacteria rather than by the body's own machinery, and it is fermentation rather than digestion.
Why traditional preparation changes the picture
Soaking dissolves a portion of those complex sugars into the water, which is then discarded. Long cooking and pressure cooking break down more of them.
Sprouting and fermenting go further still, since the seed's own enzymes and the microbes involved consume some of these compounds before the food is ever eaten.
These steps appear across Indian pulse cookery, and they alter the composition of the finished dish well before it reaches the table.
What the spices are doing alongside
Asafoetida, ajwain, cumin and ginger appear so consistently in pulse dishes that the pattern is unlikely to be coincidence. Their use is long-standing culinary practice rather than a measured intervention.
They also serve a straightforward flavour purpose, since pulses are mild and take strongly to aromatic tempering.
The two explanations are not in competition, and cooking traditions frequently keep a practice for both reasons at once.
Why pulses are paired rather than served alone
Pulses and grains carry different balances of amino acids, and a meal containing both supplies a broader range than either does by itself.
Indian meals pair them almost universally, whether as rice and dal or as flatbread with a legume dish. The combination is structural to how the plate is assembled.
Anyone with a specific dietary condition should work from advice given by a qualified professional, since individual needs vary widely and general patterns say little about any one person.