Food is any nutrient-rich material consumed or absorbed by animals and plants to sustain life and growth. It provides energy for the body, fuels metabolism and keeps cells healthy. People use various methods of food acquisition, preparation and storage to obtain the nutrients needed for optimal health. The concept of food has changed dramatically in recent history, largely due to industrialization. Originally, humankind relied on hunter-gathering and horticulture for their nutrition. Then, with the advent of agriculture and animal husbandry, food became available in more accessible forms. Moreover, it became easier to store and transport foods. As a result, a large variety of processed and fast foods came onto the market.
While it’s important to limit the intake of high-fat, salty, sugary foods, many foods can be enjoyed in small quantities and still be part of a healthy diet. For example, whole grains are a good source of fibre and phytochemicals that promote gut health. Fruits and vegetables provide vitamins and minerals that support the immune system. And, lean meats and nuts are a great source of protein and essential fats.
There are a number of steps that go into creating food products and making them available for consumption, including planting and growing, harvesting, cleaning, cooking and packaging. Some foods undergo more processing than others, which changes their taste and nutritional value. The amount of processing a food goes through also affects the energy it contains, as well as its nutritional content.
Unprocessed foods, such as whole fruits and vegetables, are a rich source of nutrients, but even these foods have undergone some form of processing. This is usually to preserve them for longer, such as through freezing or canning. Foods that have been minimally processed include raw or cooked vegetables, raw or canned fruits, unsweetened low-fat yogurt, cheese and milk.
More-processed foods, such as fried or fast food items, are a poor choice for a healthy diet. These are often loaded with calories, unhealthy fats and salt. Whenever possible, opt for grilled or baked over fried options. Alternatively, try salads, soups, stews and other light meals made with fresh or frozen ingredients, beans, lentils, fish and whole grains.
Eating a healthy diet helps to reduce obesity, which can lead to a host of other health problems. Eating more vegetables and fruit, fatty fish, whole grains, unsaturated fats (olive oil, nuts and seeds) and healthy protein sources like skinless poultry and lean beef can help lower calorie intake and increase satiety levels. Additionally, eating a wide variety of different foods helps to keep the brain healthy and elevate mood, while consuming whole foods that contain probiotics can help promote gut bacteria.