So are there any strange dietary requirements to be a Christian? Do Christians have to follow the Old Testament Jewish dietary restrictions? Should all Christians be vegetarians? These are the sort of questions that I hope to answer, using the Bible as evidence. There are many other religions with dietary requirements (Muslims and Jews don't eat pork, Hindus don't eat beef, etc.), and so it could be assumed there are rules for Christianity as well. So let's see what the Bible says about these different topics.
It depends on the Christian
The most generalized speech about Christian eating habits was made by Paul in the book of Romans. Paul said: "We must stop judging others. We must also make up our minds not to upset anyone's faith. The Lord Jesus has made it clear to me that God considers all foods fit to eat. But if you think some foods are unfit to eat, then for you they are not fit." (Romans 14:14). This is repeated later where Paul says "What you believe about these things should be kept between you and God. You are fortunate if your actions don't make you have doubts. But if you do have doubts about what you eat, you are going against your beliefs. And you know that is wrong, because anything you do against your beliefs is sin." (Romans 14:22-23). So if you personally believe you should not drink alcohol, or eat meat, or whatever, then for you it is a sin and you should not do it. If later, based on scripture and discussion with other Christians you change your mind, that's fine, but if you don't and still feel uncomfortable then just don't do it. Other Christians should try to be respectful of your decision, but at the same time you should not judge them because they are free to eat whatever they want.
The topic of food wasn't just addressed by the disciples on their own. Jesus told his disciples that anything is okay to eat: "'The food that you put into your mouth cannot make you unclean. It doesn't go into your heart, but into your stomach and then out of your body.'. By saying this Jesus meant that all foods are fit to eat. Then Jesus said 'What comes from your heart is what makes you unclean. Out of your heart come evil thoughts, vulgar deeds, stealing, murder, unfaithfulness in marriage, greed, meanness, deceit, indecency, envy, insults, pride, and foolishness. All of these come from your heart, and they are what make you unfit to worship God.'" (Mark 7:18-23). So Christians are free to eat anything, and Jesus says that sin is from the heart, not from eating the wrong food.
It depends on those around you
So, as we have seen, the first issue to decide if something is okay to eat is if you feel it is okay. If it's okay for you to eat it, then the next question is "Can I eat this when I'm with ____ ?". Again in the book of Romans, Paul said "If you are hurting others by the foods you eat, you are not guided by love. Don't let your appetite destroy someone Christ died for. Don't let your right to eat bring shame to Christ." (Romans 14:15-16), and also "All foods are fit to eat, but it is wrong to cause problems for other followers of the Lord. It is best not to eat meat or drink wine or do anything else that causes problems for other followers of the Lord." (Romans 14:20-21). This is repeated in 1 Corinthians 8:9 "Don't cause problems for someone with a weak conscience, just because you have the right to eat anything.". So if you're around someone who strongly believes that Christians should not eat ____ or should not drink _____, then in order to keep the peace and not cause them to have internal doubts and strife, it's better to not eat or drink it in front of them. Paul goes so far as to say that "When you sin by hurting a follower with a weak conscience, you sin against Christ. So if I hurt one of the Lord's followers by what I eat, I will never eat meat as long as I live."(1 Corinthians 8:12-13).
Paul then uses an example that was common back in that time as an illustration. Back then, some pagan cultures would offer food to their idols in a ceremony, and then would eat it or sell it in the marketplace. Since the Christians knew that idols are just unliving statues, it was not a sin to eat food offered to them. However, Paul says that if someone grew up believing in idols, and then converted to Christianity, then this person may have issues eating food offered to them. If they saw another Christian eating this food it could perhaps ruin their faith. (paraphrased from 1 Corinthians chapter 8).
This principle could be applied to anything: "If our faith is strong, we should be patient with the Lord's followers whose faith is weak. We should try to please them instead of ourselves. We should think of their good and try to help them by doing what pleases them." (Romans 15:1-2). For example, one shouldn't drink alcohol around a new Christian who is a recovering alcoholic, even if you will not get drunk. Another example is don't listen to heavy metal music around Christians who are convinced heavy metal music is from Satan. Note that this rule can only be applied to subjects where the Bible is not clear. For example, you can't say "I don't think it's a sin to murder, so I'm free to do it.", since murder is clearly forbidden in the 10 Commandments.
All of the following discussion is subject to these two rules: Don't eat it if you think it's a sin, or if others around you will think it's a sin. So keep that in mind when reading the rest of this article.
Should Christians be vegetarian?
This debate went on between some of the Christians even as far back as just a few years after Jesus was crucified. In the book of Romans, Paul addresses the Christians on this issue. He said "Some think it is alright to eat anything, while those whose faith is weak will eat only vegetables. But you should not criticize others for eating or for not eating. After all, God welcomes everyone." (Romans 14:2-3) Paul also said "Any followers who eat meat give thanks to God, just like the ones who don't eat meat." (Romans 14:6). There were different issues surrounding eating meat back in the New Testament than today. Today eating meat is more about environmentalism and caring for animals, where in the New Testament the issue was more about eating meat that has been offered to idols. The idols issue has been addressed by Paul in the my previous paragraph, but what about today where some people believe it is a sin to kill and eat animals?
This issue is easily resolved by looking at the Old Testament book of Genesis. After the flood, God told Noah that it was now okay to eat animals: "All animals, birds, reptiles, and fish will be afraid of you. I have placed them under your control, and I have given them to you for food. From now on, you may eat them, as well as the green plants you have always eaten." (Genesis 9:2-3). Before this point, it is likely that most people were vegetarians. This shows that God clearly says it's okay for us to eat animals, although we probably shouldn't cause them any undue pain in the process (i.e kill them as humanely as possible, don't eat them alive, etc.).
God had one rule though: "But life is in the blood, and you must not eat any meat that still has blood in it" (Genesis 9:4). This is most likely because back then they did not know about bacteria ("life in the blood"), viruses, or other diseases which are much more likely to exist in only partially-cooked meat. Today we know which meats are safe to eat partially cooked and which aren't (i.e rare steak is usually safe, but chicken needs to be fully cooked because of salmonella bacteria). So I believe this rule does not apply today, and was meant to prevent God's people from dying of easily preventable diseases from not cooking all their meat fully. Many other rules relating to food in the Old Testament were based around prevention of disease for people who had no knowledge of hygiene, such as "Don't eat the meat of any of your livestock that was killed by a wild animal. Instead feed the meat to dogs" (Exodus 22:31), and "If any of the sacred food is left until morning, it must be burned up" (Exodus 29:34). So there doesn't seem to be any problem with eating meat as long as it is cooked properly.
Can Christians eat pork?
In Leviticus chapter 11, God gives a large list of animals which are considered "unclean" and should not be eaten or touched if they are dead. This includes animals such as: camels, rabbits, pigs, any seafood besides fish, eagles, vultures, crows, seagulls, bats, insects (besides grasshoppers, locusts, and crickets), moles, rats, mice, lizards, as well as "disgusting little creatures that walk close to the ground". Due to these restrictions, the Jews do not eat pork, or any pork-related products (but I really feel sorry that they're missing out on bacon....mmmmm).
This list of animals is interesting as it is not a random list. Most people would not want to eat any of these animals in the first place (who would want to eat a seagull?), so most of these animals people would naturally avoid. Many of these animals are scavengers, which would lead to them having proportionally more bacteria and disease than other animals. Other animals such as pigs are notorious for having bacteria in them, which could make them a danger to handle or to cook. Even if the meat is cooked properly, all the tools used in preparation and the preparer's clothes and hands would be contaminated. Back before there was antibacterial soap and hot running water and washing machines, this bacteria could potentially kill someone. God did not want his chosen people to die off from bacteria, so he instituted these rules to prevent as much disease as possible. There would be no point promising a saviour would come from Abraham's race if they all died of food poisoning. So I believe that it is okay to eat pork, although it might be a good idea to avoid the other animals just because they are still known to carry diseases (and probably even more nowadays, considering our sewer systems, landfills, and pollution). However, if you're stuck on a desert island it's probably ok to eat one if you're starving to death.
Can Christians drink alcohol?
The simplest answer for this is: Yes, Christians can drink alcohol. Jesus drank wine, and one of his first miracles was to make wine at a wedding (and it was very good wine too, proving Jesus had good taste in alcohol) (John 2:1-10). Jesus said he will even drink wine in heaven: "From now on I am not going to drink any wine, until I drink new wine with you in my Father's kingdom." (Matthew 26:29). So if Jesus can drink wine, the rest of us can too. Wine was the most common alcohol back in New Testament times, however I'm sure that if Jesus were around, he would be drinking beer and preaching in a bar to those who need to be saved. There is nothing wrong with enjoying alcohol in moderation, as long as you don't put others in danger by driving under the influence.
There are some Churches which ban alcohol consumption completely by their members (the Wesleyan and Nazarene denominations are known for this). This is probably because they feel it is better to avoid it completely than to risk getting drunk or addicted. There is some basis for this in 1 Timothy 3:8-11, where it is recommended that church leaders should not be "heavy drinkers", but it doesn't forbid alcohol entirely. However, many Christians feel it is better not to drink alcohol at all, and so this may lead to a situation where if you feel it is okay, but someone else you are eating with feels it's a sin (and you know about it beforehand), then it might be better to avoid it. If you don't know they think it's a sin, but they later point it out, just say that you're okay with it and mention that Jesus drank wine, and keep a mental note to not do it next time you're out with that person.
It is important for Christians to avoid addiction or dependency on alcohol. When Paul wrote to the Corinthians, he told them "Some of you say 'We can do anything we want to.'. But I tell you that not everything is good for us. So I refuse to let anything have power over me." (1 Corinthians 6:12). We are supposed to honor God with our bodies, and getting drunk does not match with this. "You surely know that your body is a temple where the Holy Spirit lives. The Spirit is in you and is a gift from God. You are no longer your own. God paid a great price for you. So use your body to honour God." (1 Corinthians 6:19-20).
Should Christians fast?
Often in the Bible there were times when people would fast (i.e go without eating, either fully or partially), most often to show to God that they are sincere about their prayers to God on a specific subject. Some examples of this are in the book of Esther, when Esther asked the entire Jewish population to fast while she risked her life to save them (Esther 4:16). King David fasted when his son was ill and dying (2 Samuel 12:16), and Jesus fasted for 40 days in the desert before he started his 3 years of teaching (Matthew 4:2). The disciples also fasted occasionally after Jesus had left and they were with other church members. So there is Biblical evidence for fasting, and some Christians today still choose to fast when they are praying really hard for something. However, there is no requirement to do this, and it is optional. Personally, I do not fast, because if I go without food for more than 8 hours I easily become cranky and exhausted, which does not increase my desire to pray. Also, some Christians cannot fast, such as those with diabetes who must regulate their meals for health reasons.
There is a guideline for Christian fasting given in Matthew 6:16-18: "When you go without eating, don't try to look gloomy as those show-offs do when they go without eating. I can assure you that they already have their reward. Instead, comb your hair and wash your face. Then others won't know that you are going without eating. But your Father sees what is done in private, and he will reward you.". So Christians who do decide to fast should not make a big deal over it and try to show off to other Christians who do not fast. Deciding to fast does not make one more spiritual, and although it shows you are sincere to God, it cannot be used as a way to manipulate God. God knows your heart, and if you are using fasting to try to get what you want, and think that God has to give you what you are asking for, then you probably won't get it.
In some Christian circles there is a tradition to "fast" from one thing during the period of 40 days before Easter (this period is called "Lent"). Some Christians decide to give up something that they like for this period of time (such as coffee, television, chocolate, etc.) to prove that they are not dependent on it and that God is the only one they truly need. While this does perhaps help some Christians, there is no Biblical requirement to do this and it is optional.
Conclusion
So as we have seen, Christians are free to eat anything, including meat, pork, and alcohol. The more important aspect is that if you believe you should not eat something, then don't, because it is a sin for you. Also, if it would make anyone around you think that you are sinning, or convince them to go against their beliefs, then it is a sin. So Christians should try to discern when it is appropriate to eat/drink something and when it is not. Don't judge other Christians for something as minor as what they eat or drink. Jesus said "The kingdom of God isn't about eating and drinking. It is about pleasing God, about living in peace, and about true happiness."(Romans 14:17).
There will probably be some people who still judge you though no matter what, probably the more religious types who believe they are right and everyone else is wrong. Jesus says sometimes there are no-win situations with these sorts of people, such as the Pharisees back in his day. Jesus said to them "John the Baptist did not go around eating and drinking, and you said 'John has a demon in him!'. But because the Son of Man goes around eating and drinking, you say, 'Jesus eats and drinks too much! He is even a friend of tax collectors and sinners. Yet wisdom is shown to be right by what its followers do."(Luke 7:33-35). So if you meet one of these people who criticize everything, just ignore them. They are like the person that Jesus described as "You can see the speck in your friend's eye. But you don't notice the log in your own eye."(Luke 6:41) when they try to criticize a tiny thing in another Christian (such as what they eat) but ignore the much larger issues of being called to love one another, and extending God's grace and mercy and forgiveness to people. Eat what you think is right, and be sensitive to others, but we are called to love others and love God, and those are the main points Christians should focus on.