List some of the main threats to the global food supply
• Hunger, poverty, and population growth. By 2050, 1 billion additional tons of grains will be needed to feed the world's population; food increase may not be possible beyond the earth's human carrying capacity.
• Loss of food-producing land. Food-producing land is becoming saltier, eroding, and being paved over and the world's deserts are expanding.
• Fossil fuel use. Fossil fuel use underlies much world economic growth, with associated pollution of air, soil, and water.
• Atmosphere and global climate change. Strong evidence indicates that recent warming is largely caused by human activities, especially the release of greenhouse gases through the burning of fossil fuels. The associated heat waves, droughts, fires, storms, and floods thwart farmers and destroy crops, particularly in the poorest areas of the world. Arid deserts are projected to expand by 200 million acres in coming years in Sub-Saharan Africa alone. As ocean heat builds up, ocean food chains may fail.
• Ozone loss from the outer atmosphere. The outer atmosphere's protective ozone layer is thinning, permitting more harmful radiation from the sun to penetrate. As radiation increases the earth's temperature, polar ice caps are melting, threatening the world's coastlines. Radiation may also directly damage important crops.
• Fresh water shortages. Growing food requires great quantities of fresh water. The earth's fresh water supply is unevenly distributed, and too much of it is wasted, polluted, and unsustainably managed. Over a billion people lack access to fresh water today. If climate change continues on its current trajectory, almost half the world's population may be living in areas of high water stress in just 20 years from now; water scarcity could displace many millions of people from their homelands.
• Increased flooding. Crop-damaging localized heavy storms are expected to become more frequent, causing flash floods that erode large swaths of topsoil from parched land.
• Ocean pollution. Ocean pollution, particularly agricultural and industrial runoff, is killing fish in large "dead zones" that form when excessive algal growth depletes water oxygen; dead zones are expected to expand as sea temperatures rise.
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A dietitian is providing nutrition information to a patient with a jaw fracture who has had a maxillomandibular fixation. Which type of food would the dietitian most likely tell the client to avoid?
A. rye bread B. 2% milk C. bananas D. pasta E. soft-cooked eggs
Malnutrition associated with poor intake appears to have an impact on the strength and endurance of respiratory muscles, particularly the diaphragm.
Answer the following statement true (T) or false (F)
The World Health Organization (WHO) recommends that all governments prohibit the feeding of highly innervated tissue from slaughtered cattle to other animals because:
A) these tissues cannot be digested by most animals. B) bacteria in these tissues are not killed even at high temperatures. C) prions are found mainly in the brain and spinal cord. D) they are high in cholesterol making it an unhealthy feed for cattle.
Karl is taking a nutrition class and has decided that his diet needs improvement. He has learned about many different types of foods, nutrients, and health problems associated with the diet. Some of Karl's biggest dietary concerns include losing body fat, increasing dietary fiber, and decreasing his late-night snacking. Karl normally skips breakfast to be able to sleep the extra 15 minutes before
running to his first class of the day. His first meal of the day is around 3 p.m. and consists of convenient foods found in the university union such as Chinese food, a burger and fries, or a few slices of pizza and a cola. After his afternoon lunch he relaxes with friends who often play video or computer games. Around 8:30 p.m. Karl and his friend order take-out or drive to the nearby fast-food restaurant for a tasty meal before starting to study. Throughout his night time studying Karl snacks on potato chips, pretzels, and more cola. Karl's bed time is around 1 a.m. Which of the following lifestyle changes would be helpful for Karl in his attempt to lose body fat? A) Start smoking B) Start playing basketball with friends after class instead of playing video or computer games C) Go on a high-protein, low-carbohydrate diet D) Start taking an afternoon nap instead of playing video or computer games