The Torah does not command us to be ascetic or to fast, as fasting is like taking medicine for an illness, whereas eating for the sake of Heaven is the healthy and proper way to live:

Part of the perfection of the Torah is that it commands us to fast on only one day of the year, revealing the underlying intention of the mitzvot, which is that one should walk the middle path [and not behave in an extreme fashion]. This is unlike the teachings of other nations, who have tried to imitate our Torah. When one eats for the sake of Heaven, it is better than fasting, because fasting merely heals the disease of excessive desire, but eating for the sake of Heaven is considered an act of righteousness. (Rav Yaakov Anatoli, Malmad HaTalmidim, Nitzavim)

At every moment, and with every act, one must serve God. This applies even while eating, which is when one is apt to forget Him. One must be particular to eat only the amount necessary to sustain his body, and must not eat in order to fulfill his desires.

Even while eating, one must cling to God:

Even while eating, when you are close to forgetting Him and separating your mind from the knowledge of Him, “Be cognizant of Him” (Proverbs 3:6), cling to Him. If you do this, then [as the verse concludes], “He will smooth your paths” (Proverbs 3:6); God will smooth the way for you on the path of life. This is referring to the triumph of the soul [when it receives its portion] in the World to Come.

One must eat only in order to sustain the body, and not out of desire:

Therefore, it is fitting for a person to eat only for the subsistence of the body. It is forbidden for him to be drawn to any indulgence unless it replenishes his body and opens his mind, so that his body is healthy and strong, subject to his will and the will of his Creator…. One who has this intention is considered “an angel of the Lord of hosts” (Malachi 2:7). But one who does not have this as his objective “is like the beasts that perish” (Psalms 49:13). (Rabbeinu Baĥya, Shulĥan Shel Arba 2)

Further reading: For the halakhot of mealtimes, see A Concise Guide to Halakha, p. 513.

The spiritual force of permitted foods comes from the husk of Venus, which contains both good and evil. When one makes use of food in the correct way, he reveals the good in it and elevates it to a level of holiness.

The spiritual force of kosher foods comes from the husk of Venus.

The souls of pure animals, birds, and fish that are permitted for consumption, and the existence of every inanimate object and every plant that may be eaten…are dependent on the second level of the husks and the “other side,” which is the fourth husk, called the husk of Venus…which is in between the three completely impure husks and the aspect of holiness. Therefore, it is sometimes included among the three impure husks.… And it is sometimes included in the aspect of holiness [when used properly by people].

Eating as part of one’s service to God elevates the food to the level of an offering:

For example: If one eats rich beef and drinks spiced wine to expand his understanding of God and his Torah in the manner that Rava described: “Wine and good scents [make me wise]” (Yoma 76b), or in order to fulfill the mitzva of enjoying Shabbat and festivals, then the spiritual force of the meat and wine, which came from the husk of Venus, has been refined, and ascends to God like an offering. (Rabbi Shneur Zalman of Liadi, Tanya, Likutei Amarim 7)