1) to unite us to Himself and nourish our souls with His divine life;
2) to increase sanctifying grace and all virtues in our soul;
3) to lessen our evil inclinations;
4) to be a pledge of life ever lasting;
5) to fit our bodies for a glorious resurrection;
6) to continue the sacrifice of the cross in His Church.

With help from Thomas Aquinas, saint and doctor of the Church, I will now describe Holy Communion as a means to lessen our evil inclinations.

We are all born with original sin.  And although baptism removes the stain of that sin, the effects of original sin remain, i.e. we are prone to suffer and die, we are weak to do the right thing and often confused about the right thing to do.  Put another way, we are by our fallen nature inclined to seven vices.  Naturally, we are prone to gluttony, pride, lust, anger, covetousness, envy, and sloth. (G.P.L.A.C.E.S.)  Again, by nature, we love ourselves too much and in the wrong way; we will eat too much and be too finicky about what we eat; we look at people as objects and not as persons created in the image and likeness of God.  All this may be summarized by saying, even after baptism, we are inclined towards evil.

In his summa of theology, St. Thomas asks the question (Summa III, Q.79.a6) whether a man is preserved from future sins by the sacrament of Holy Communion.

In reply, St. Thomas says, sin is the spiritual death of the soul.  Hence, a man is preserved from future sin in the same way as the body is preserved from future death.  And this occurs in two ways.
First, by man being strengthened inwardly against decay.  Thus, in this way, man preserves himself from death by consuming food and drink.
Second, by man being guarded against outward assaults.  Thus, and in this way, man protects himself against an intruder by taking up arms of defense.

As one is preserved and defended against physical harm, so does a worthy reception of Holy Communion preserve and protect our spiritual well-being.

Again, and firstly, by uniting man with Christ, Holy Communion preserves and strengthens man’s spiritual life as a spiritual food and a spiritual medicine.  Here may be applied that verse in the Psalms which speaks of the bread that strengthens the heart of man, “... that wine may cheer and bread strengthen the heart of man.” (Ps 103:15)  In this sense too, St. Augustine encourages Christians who are not aware of a serious sin on their soul but yet hesitate to approach so holy a sacrament saying, “receive without fear; it is food, not poison.”
 And, secondly, in as much as Holy Communion is a sign of Christ’s passion, whereby devils flee and are conquered, so does Holy Communion repel attacks of the devil by way of spiritual weaponry.  St. John Chrysostom refers to this when he speaks of those who worthily consume Holy Communion as “lions breathing forth fire, having been made terrible to the devil.” 

So there you have it, a worthy reception of Holy Communion preserves a man from sinning in the future and works to lessen his evil inclinations.

But to obtain these effects of Holy Communion, we must receive properly which means we must know Whom we are receiving, namely, the God-Man, Jesus Christ.  Knowing this we must nurture a spirit of reverence, awe, gratitude before receiving.  And after receiving, and after Holy Mass ends and the priest has left the sanctuary, resist the impulse to leave.  Rather, linger in sweet conversation with your Christ Who yet resides within you.  Catholic doctrine teaches that Christ is present in the Sacred Host as long as the appearance of bread remains.  Theologians commonly teach that the Host takes fifteen minutes to digest before, thereby, losing its appearance as bread.  So linger there in your pew a few moments to say goodby to your divine Guest.  That is the way to show you appreciate His coming to you and harvest more grace for salvation.

Thank Him for His benefits, speak to Him of your needs, ask pardon for your negligence and sin.

This is the way to harvest an abundance of grace.  Grace that will unite us more strongly to Christ and virtue and lessen within us our inborn inclinations to vice and sin. 

Finally, I leave you with the following consideration: there are foods to fight disease, foods to cause weight loss or gain, foods to lower cholesterol, but there is no other food on this entire earth than the Holy Eucharist whereby we are helped against sin.

Suppose Holy Communion did cause weight loss, caused facial clearing, or caused improved body tone or some other worldly gain,... do you think then you would receive with more joy, more wonder, more longing, - in short - with better dispositions?  For, surely, if this were true of the Most Blessed Sacrament, the world would flock to the Real Presence.  Oh, but God wishes to give us an eternal kingdom by helping us not to sin more than He wishes to decrease our weight.

So while the world runs to its vitamins and diet drinks, let us run with greater fervor to the Blessed Sacrament.  We may not shed pounds off our mortal frame but, if properly disposed, we will come closer to heaven.