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Food

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Food is any substance that an organism consumes to gain nutritional support. It provides the energy required to maintain life, support growth, and ensure overall health. Most food originates from plants, animals, or fungi. These substances contain essential nutrients like carbohydrates, fats, proteins, vitamins, and minerals.

Good Food Display - NCI Visuals Online
Good Food Display - NCI Visuals Online

Water is present in nearly all foods and is often defined as food itself. While water contains no food energy, fat is the most energy-dense component found in nutrition.

In nature, food moves through a complex web of interlocking chains. At the base are primary producers, such as algae, plants, and certain bacteria. These organisms use photosynthesis to create energy. Photosynthesis is a process where sunlight, water, and carbon dioxide are transformed into oxygen and glucose. The glucose serves as a vital energy reserve.

Aquatic food web
Aquatic food web

Following these are primary consumers, which are herbivores that eat the plants. Secondary consumers are carnivores that eat the herbivores. At the top of the chain sit apex predators, which have no known predators in their ecosystem. Humans are classified as apex predators.

Plants are a massive source of human nutrition and can be categorized in many ways. Botanically, a fruit is the part of a plant derived from reproductive tissue. This means that many items we call vegetables, such as tomatoes, peppers, and eggplants, are technically fruits. Grains are seeds harvested by humans, such as wheat, rice, and corn. Corn, wheat, and rice are incredibly important, accounting for 87% of all grain production worldwide.

Foods (cropped)
Foods (cropped)

Vegetables include other plant parts like roots, stems, leaves, and flowers. For example, carrots are roots, while broccoli consists of flowers.

Animals also provide essential nutrients, particularly complete proteins. A complete protein contains all the essential amino acids a human body needs. For instance, a 4-ounce steak or chicken breast provides about 30 grams of protein. One large egg contains 7 grams, while a 4-ounce serving of cheese provides 15 grams.

Meatfoodgroup
Meatfoodgroup

Animal products also offer vitamins like B12 and minerals such as zinc and iron. Humans consume these animals directly as meat or indirectly through products like milk and eggs.

Microorganisms like bacteria play a hidden but critical role in the food system. Some bacteria obtain energy by breaking down dead organisms or waste. Others form symbiotic relationships to obtain nutrients. Bacteria are essential because they convert atmospheric nitrogen into ammonia. Ammonia is a necessary precursor for making proteins and vitamins.

Aquatic food web
Aquatic food web

Most of the world's ammonia is now produced by humans through a method called the Haber-Bosch Process.

Modern food is largely managed by a massive industrial food industry. This system uses intensive agriculture to grow crops and complex distribution networks to move them. This industrial approach relies heavily on fossil fuels. Consequently, food and agricultural systems are major contributors to climate change. They are responsible for as much as 37% of total greenhouse gas emissions.

Global thinking
Global thinking

This system affects many social and political issues, including water supply and biological diversity.

Because the food system is so large, international agencies must monitor it closely. These organizations focus on food safety and food security. Groups like the World Food Programme and the Food and Agriculture Organization work on these issues.

They help manage how food is grown, processed, and shared across the globe. Maintaining a stable food supply is a central challenge for human populations and the planet's ecosystems.

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🖼️ Images & Media (8)
File:Goblet Glass (Banquet).svg
Goblet Glass (Banquet).svg
File:Foodlogo2.svg
Foodlogo2.svg
File:Global thinking.svg
Global thinking.svg
File:Good Food Display - NCI Visuals Online.jpg
Good Food Display - NCI Visuals Online.jpg
File:Foods (cropped).jpg
Foods (cropped).jpg
File:Channelcat.jpg
Channelcat.jpg
File:Aquatic food web.jpg
Aquatic food web.jpg
File:Meatfoodgroup.jpg
Meatfoodgroup.jpg
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