The Deipnosophists (2.42)

Diodes asserts that almonds are nutritious and good for the stomach, and that they have a heating effect because they contain something like millet; but green almonds are less likely to have an injurious effect than dry ones; and almonds soaked in water have such an effect less than those which are not soaked; and when toasted less than when raw. But walnuts, which are also called nuts of Heraclea, and acorns of Jupiter, are not indeed so nutritious as almonds, but still they have something like millet in them, and something apt to rise to the surface; so, if they are eaten in ay quantity they make the head feel heavy; they, however, are less likely to produce injurious effects when green than when dry.

Persian nuts too are as apt to produce headches as the acorns of Jupiter; but they are more nutritious, though they make the throat and mouth feel rough; but when they are roasted they are less injurious, and when eaten with honey, they are the most digestible of all nuts The broad Persian nuts

The broad nut, and that which is called the Sardinian nut, are both exceedingly indigestible when raw, and are very slow in dissolving in the stomach, as they are kept down by the phlegm in the stomach, and as they themselves are of an astringent nature. The Pontic nut too is oily and indigestible; but the almond is not so indigestible as that, and accordingly if we eat a number of them we do not feel any inconvenience; and they appear more oily, and give out a sweet and oily juice.

Diphilus of Siphnos says—

There is a nut called the Royal nut, which causes severe headaches, and keeps rising in the stomach; and there are two sorts of them, one of which, that which is tender and white, is the more juicy and the better; but that which is roasted in ovens is not nutritious. Almonds have a tendency to make people thin, and are diuretic and cathartic, and far from nutritious; and the dry ones are far more apt to produce flatulence and are far more indigestible than the green ones, which do not give much juice, and which are not very nutritious; but those which are tender, and full, and white, being like milk, are more full of wholesome juice. And the Thasian and Cyprian nuts, being tender, are far more easily digested than dry ones. The nuts of Pontus are apt to produce headaches, but still they are not so indigestible as the Royal nuts.