With rising food prices, growing population and environmental problems, many people are worrying about how we will feed ourselves in the future. Don't worry. Scientists are trying to find some answers. Some scientists believe insects will become a staple of our diet. Insects provide as many nutrients as ordinary meat and a great source of protein  , they also cost less to raise than cows and use less water. About 1,400 species are suitable as food for humans. Many people have already eaten insects as a part of their diet. Locusts are popular in Africa, wasps are a dish in Japan, and crickets are eaten in Thailand. The Dutch government is preparing for insect farms and has invested one million euros into research. In the future, land and fresh water will be in short supply. It is possible that people need to find a reliable food source in the ocean. Scientists have already found one at the bottom of the food chain---seaweed. It has long been a staple in Asia, and countries including Japan have huge seaweed farms. Such farms can easily work in other countries and be very successful. The great thing about seaweed is that it grows at an amazing rate. It's the fastest growing plant on earth. Scientists are also working in the lab to solve the problem of food shortage. A few years ago, European scientists successfully produced lab meat, also known as cultured meat. They grew muscle tissue using stem cells taken from cows. The experiment was funded by NASA to see if lab meat was a food astronauts could eat in space. In 20 years' time , lab meat is likely to become a popular dish of our diet. According to research, growing meat in a lab rather than slaughtering  animals can greatly reduce greenhouse gases, along with energy and water use. People can also reduce fat from the meat and add nutrients. How many kinds of future food are introduced in the passage?
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