It is easy to read a passage such as this and think it does not apply to us today. In general we do not see the dietary struggles that the early church experienced because we are not trained with the Old Testament laws and regulations they were trained in. However the underlining principal that Paul is addressing in this passage still applies today.
First we are to judge ourselves to make sure we are not causing others to stumble by our actions. This should be a mindset not to use our freedom to destroy the faith of our brethrens. Paul was fully convinced that no food was unclean but it was how that food was received that made it unclean for that individual. If they weren't receiving from faith then to them it was unclean. Sometimes these truths take a while to take hold in our lives. Paul told Timothy, "For everything God created is good, and nothing is to be rejected if it is received with thanksgiving, because it is consecrated by the word of God and prayer" ( I Timothy 1:4-5 ). Everything that God made is good and nothing has to be refused if we receive it with thanksgiving and from faith.
This struggle between the old covenant law and the new and better covenant that we enjoy today extends far past dietary laws of eating and drinking. Early Christians struggled over these things because they did not understand that they were a shadow of the things to come. Colossians 2 speaks directly to this very thing, "Therefore do not let anyone judge you by what you eat or drink, or with regard to a religious festival, a New Moon celebration or a Sabbath day. These are a shadow of the things that were to come; the reality, however, is found in Christ" ( Colossians 2:16-17 ). Likewise today, some Christians still hold to Old Testament ritual without any idea that the ritual has become reality in Christ. But now that Christ has come, the rituals are meaningless and can become oppressive. This is why it is important to fully understand the differences in the covenants so we can walk in the freedom and liberty that Christ purchased for us, ratifying it with His precious blood.
The bottom line is that we are all in different stages of maturity in Christ. We should encourage one another and we should decide to walk in the freedom that Christ has revealed to us while making up our minds not to cause our brothers and sisters in Christ to stumble in their faith by our actions. How we do this is by loving our neighbor as ourselves. In the previous chapter Paul summarized that our duty was to love and act in love toward one another ( Romans 13:10 ). If we ignore the influence our actions have on others, we are not walking in love. So we must continue toward the freedom into which we have been called while loving and extending grace and patience with our fellow believers.