This chapter explores how to consistently maintain a balanced and varied diet in a society that often presents unhealthy choices. Unlike physical activity, which can feel optional in our modern world, eating and drinking are essential for survival. Thus, managing your eating habits requires skills different from managing your physical activity.
Every time you have the chance to eat or drink, you must make decisions about your diet. While nutrition advice is constantly changing, the fundamentals of a healthy diet are more apparent than they appear. A key to making consistent healthy choices is to plan to have healthy foods you enjoy readily available, which can help you resist unhealthy temptations.
Eating Well: Balanced and Clean
“eating clean” generally refers to consuming foods in their most natural forms. The term “processed” often carries a negative connotation, and many people associate processed foods with high levels of added sugars, salt, and preservatives. However, processing refers to altering a food product before consumption. This can include freezing, pasteurizing, cooking, canning, preserving, baking, and fortifying with vitamins and minerals. Thanks to processing, we can enjoy a variety of foods throughout the year, consume safer products, and avoid nutrient deficiencies. While eating clean is beneficial, being overly rigid in this practice can often be impractical and sometimes unsafe.
Beyond Calories to Fuel Quality
Many people simplify nutrition by focusing solely on the energy content of food or calories. However, the quality of what you eat is equally important. Just as putting low-quality fuel into your car will cause it to run poorly, consistently providing your body with low-quality food will hinder its performance. This “running well” goes beyond physical exercise; it encompasses your daily activities on campus, including mental concentration, motivation, and mood management. To maintain good long-term health, it is essential to reduce the risk of major metabolic issues, such as cardiovascular disease, diabetes, and cancer, introduced in Chapter 4, as well as osteoporosis and sarcopenia discussed in Chapter 7 and other chronic health conditions.
Essential Nutrients: A helpful perspective for maintaining a healthy diet is focusing on the taste and enjoyment of foods and drinks and the nutrients they provide. Your diet should include approximately 45 essential nutrients. These nutrients are considered necessary because your body cannot produce them independently, or doing so may lead to other health issues. The six main categories of essential nutrients include macronutrients (carbohydrates, fats, and proteins), micronutrients (vitamins and minerals), and water.
Cories:What comes to mind when you hear the word “calorie”? Is it something to be feared that can lead to unwanted weight gain? Or is it something you need for energy to get through the day? Do you think of this term when reading food labels?
A calorie is a unit of energy that describes various scientific processes. More accurately, a calorie refers to a kilocalorie, which is how we express energy from foods. Since most people are familiar with the term “calorie,” which is used on all food labels, we will use it in this book instead of “kilocalorie.”
Figure 8.1 lists the three primary macronutrients in order of their energy density. It’s important to note that while alcohol is neither a macronutrient nor considered essential, it does contribute calories to your daily energy intake.
Energy Needs:Several factors, including age, sex, Height, weight, physical activity, and health conditions, influence energy needs. The dietary guidelines in this chapter provide estimates of energy requirements based on these factors and specific circumstances, such as pregnancy or illness. Moreover, a person’s motivation to lose, gain, or maintain weight can influence their energy needs and activity levels. Chapter 9 explores energy requirements in greater detail.
Carbohydrates Great Energy Sources
During the digestive process, carbohydrates are broken down into glucose, which the body uses for energy. Excess glucose is stored in the liver and muscles as glycogen. Carbohydrates are the body’s primary power source, and glucose is the brain’s exclusive energy source. They provide working muscles with readily available energy, especially during high-intensity exercise. From an energy storage perspective, carbohydrates are stored in much smaller amounts in the body compared to fat and protein.
When thinking about foods containing carbohydrates, bread, potatoes, pasta, and cookies may come to mind, but carbohydrates are present in most foods. Among the three macronutrients, carbohydrates contribute the most to daily caloric intake.
Carbohydrates can be divided into two main categories: simple and complex carbohydrates. Complex carbohydrates can be divided into refined and whole grains (Institute of Medicine, 2005).
Simple Carbohydrates:Your taste buds recognise simple carbohydrates due to their sweetness in foods. While they naturally occur in fruits and milk, simple carbohydrates are also found in soft drinks, fruit drinks, candy, desserts, yoghurt, condiments, and plant-based milk such as soy milk.
Bere of Added Sugars:Added sugars are not naturally present in foods that consumers or manufacturers incorporate. For instance, if you add brown sugar to your oatmeal or honey to your tea, you are including added sugars in your diet. Sugars that are naturally found in fruits or milk are not considered added sugars. Many foods containing added sugars are of low nutritional quality, providing excess calories and minimal nutritional value. In addition to raising the risk of obesity and other metabolic diseases, added sugars are also associated with tooth decay and cavities.
In the United States, added sugars are a significant public health concern, contributing approximately 270 calories, or 13 per cent, of daily caloric intake. The primary sources of added sugars are sugar-sweetened beverages, sweet snacks, and desserts. Sugar intake should be limited to 10 per cent of daily caloric intake(U.S. Department of Health and Human Services & U.S. Department of Agriculture, 2015).
While it is often easy to identify intentional sugar additions, such as a scoop of sugar in your morning coffee, hidden sources in packaged foods can be more challenging to recognise. These products may include flavoured yoghurts, peanut butter, processed fruit drinks, and snacks. Checking the ingredient list or food label for added sugars can help you make informed food choices.
Types of Carbohydrates
Simple carbohydrates (sugars): Lack vitamins, minerals, and fiber | Complex carbohydrates: Provide vitamins, minerals, and fiber |
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Monosaccharides: single-sugar molecules | Starches: long, complex chains of sugar molecules |
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Disaccharides: double-sugar molecules | Fiber (nondigestible carbohydrates) |
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Micronutrients: Vitamins and Minerals
Vitamins and minerals, while calorie-free, are essential for maintaining good health. These nutrients can be found in whole foods such as fruits, vegetables, and grains and processed foods such as flour and breakfast cereals, which often have added vitamins and minerals.
Although deficiencies in vitamins and minerals are uncommon, many Americans fail to meet the recommended intake of essential nutrients, which can lead to chronic health issues later in life. It’s critical to evaluate your individual vitamin and mineral needs based on age and gender. Access to nutritious food is crucial for proper nutrient intake; deficiencies can develop and lead to noticeable symptoms without it.
Vitamins:Vitamins are organic compounds needed in small amounts to facilitate the body’s chemical processes. They are essential for producing various functions in the body. Vitamins E and C and beta-carotene (a precursor to vitamin A) are recognised as antioxidants. Antioxidants help block the formation and effects of free radicals, substances produced during normal metabolic processes that can contribute to ageing and cancer. Furthermore, antioxidants are part of a larger group called phytochemicals, found in plant foods and help prevent chronic diseases.
In addition to the vitamins obtained from food and supplements, some vitamins are produced by the body. For example, vitamin D is synthesised in response to sunlight, and vitamin K is generated through processes involving intestinal bacteria. However, it is still important to consume vitamins D and K for optimal health (Institute of Medicine, 2005; U.S. Department of Agriculture, n.d.b).
Humans require 13 essential vitamins categorised as nutrients, which can be classified as fat-soluble or water-soluble, depending on how they are absorbed, transported, and stored in the body. The four fat-soluble vitamins (A, D, E, and K) are carried by special protein carriers in the blood and stored in the liver and fat tissues, hence the term “fat-soluble.” In contrast, the nine water-soluble vitamins (B, B12, biotin, C, folate, niacin, riboflavin, thiamin, and pantothenic acid) are absorbed directly into the bloodstream and circulate freely. Water-soluble vitamins are removed by the kidneys and excreted in urine. Due to these differences, experiencing an excess of water-soluble vitamins is less common than fat-soluble vitamins (Institute of Medicine, 2005).
Minerals:Minerals are inorganic elements that are vital for human health. They play an essential role in regulating various bodily processes., promoting the growth and maintenance of tissues, and producing energy. Among the 17 essential minerals, the key ones required in amounts greater than 100 milligrams per day include calcium, chloride, phosphorus, magnesium, potassium, and sodium. Additionally, essential trace minerals are needed in tiny amounts, such as copper, fluoride, iodine, iron, selenium, and zinc (Institute of Medicine, 2005; U.S. Department of Agriculture, n.d.b).
Too Much and Too Little:Unless an individual has very unusual eating habits—possibly due to an eating disorder—or is excessively consuming vitamin and mineral supplements in pill or powder form, the likelihood of excessive intake of these nutrients is rare. Fat-soluble vitamins pose the most significant concern because they are stored in the body, which can increase the risk of toxicity.
Inadequate intake of vitamins and minerals, especially those listed in Table 8.4, is quite common. Chronic poor nutritional habits are more prevalent than actual dietary deficiencies. These poor habits can lead to an increased risk of chronic diseases later in life, including heart disease and osteoporosis.
Most Americans who maintain a varied and nutritionally balanced diet on most days do not need to take supplements to meet their vitamin and mineral needs. Relying on supplements for most vitamins and minerals can also result in missing out on other essential substances found in food, such as fibre. Colourful fruits and vegetables are rich sources of critical vitamins, minerals, fibre, and energy!
The Importance of Hydration
Hydration is an important yet often overlooked aspect of health. Water makes up 50 to 60 per cent of our body weight, which makes it a vital nutrient. While the human body can survive for several months without food (depending on its size and composition), it can only last a few days without water. Water is essential because it serves as the medium for chemical reactions, helps regulate body temperature, and is the primary component of blood.
We continuously lose water through urine, faeces, evaporation during breathing, and, of course, through sweating. Therefore, maintaining proper hydration is vital for overall health and well-being.
Essential Vitamins and Minerals Commonly Lacking or Excessive in Young Adults
Common dietary source | Major function | |
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Vitamin A |
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Vitamin C |
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Vitamin D |
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Folate |
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Calcium |
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Iron |
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Magnesium |
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Sodium |
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Potassium |
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The Many Benefits of a Healthy Diet
Now that you have been introduced to the primary considerations for achieving a balanced and clean diet let’s discuss the motivational reasons for managing your eating habits. Why is it essential for you to eat healthy? Take a moment to reflect on what influences your food choices, such as family traditions, college friends, your mood and stress levels, or even your budget. Whatever your reasons, there are numerous benefits to consuming a healthy diet that can positively impact your well-being now and help you become a healthier version of yourself in the future.
Weight Management
Managing energy balance can be challenging. If you need help understanding calorie counting and how calories might be hidden in your diet, you may find it difficult to maintain weight. For instance, many people must know how many calories come from their beverages, such as sweetened sodas, sports drinks, coffees, and teas. You’ll better understand your dietary choices by learning about macronutrients and their associated calorie counts.
Feeling and Performing Better
Fuel quality and hydration are crucial for optimal physical, mental, or social performance. Dehydration can leave you feeling sluggish, which may diminish the quality of your day. Skipping breakfast can lead to low blood sugar. Symptoms like shakiness or headaches may occur by mid-morning, especially during essential classes. It is crucial to remember that your nervous system, particularly your brain, relies on glucose as its primary fuel source. Therefore, managing your blood sugar can improve your ability to concentrate. Additionally, consuming too much caffeine can heighten anxiety. Ultimately, your eating and drinking habits directly impact how you feel and how well you perform.
Investment in a Healthier Future Version of Yourself
Diet plays a crucial role in weight management and influencing the risk of various chronic diseases, notably the “Big Metabolic Three,” along with conditions related to body composition, such as osteoporosis and sarcopenia. Although these chronic diseases often develop during middle age or in older adults, maintaining a healthy diet can significantly affect their risk factors.
Nutrition Recommendations and Resources
Many diets can be healthy and balanced, providing various options that cater to our food preferences and budgets. However, the sheer number of daily food choices can make it challenging to make healthy decisions consistently. So, how can we determine what to eat and drink to achieve optimal health? Scientists and government agencies have collaborated to provide recommendations and resources to help you create a personalized nutrition program. Additionally, you can use apps to track your dietary habits. It’s important to source high-quality food, and it is advisable to consult a registered dietitian, especially if you face specific nutritional challenges such as food allergies.
Dietary Reference Intakes
The Dietary Reference Intakes (DRI), published by the Food and Nutrition Board of the Institute of Medicine, set standards for nutrient intake that help prevent nutritional deficiencies and lower the risk of chronic diseases.
Four specific reference values exist for recommended intakes and optimal safety:
- Estimated average requirements refer to nutrient intake levels designed to meet the needs of half of healthy individuals within a specific group.
- The Recommended Dietary Allowance (RDA) is the average daily intake that meets the nutrient needs of approximately 97 to 98 percent of healthy individuals.
- Adequate intake is determined when there is insufficient evidence to develop a Recommended Dietary Allowance (RDA) and is established at a level presumed to ensure nutritional adequacy.
- The tolerable upper intake level refers to the maximum daily amount of a nutrient unlikely to cause adverse health effects. While having lower nutrient levels than recommended is common, consuming more than recommended can sometimes be beneficial or harmful. We encourage you to explore the free interactive resources that are available.
Calcium Intake
Now
Few people meet their recommended calcium intake because of the quality of many diets. Some of the best calcium sources are low-fat dairy products such as milk and yogurt. If you do not like milk or are lactose intolerant, try to get calcium from other sources in your diet, such as broccoli or fortified orange juice. The intake recommended for young adults is 1,000 milligrams per day; this includes food and supplements (U.S. Department of Health and Human Services and Department of Agriculture 2015).
Later
The calcium recommendation increases to 1,200 milligrams daily for older men and women. Because of the loss of estrogen for women and changes in hormones that occur with the ageing process for all people, bone loss rapidly increases after middle age. People with low calcium intake have accelerated bone loss.
Take Home
To reduce your risk of bone fracture later in life, build your bone bank by getting enough calcium in your diet. If you do not like dairy or other foods that contain calcium, consider a suppleme
Mediterranean-Style Eating PatternThis diet is characterized by patterns common in cultures of the Mediterranean region. It includes frequent consumption of unsaturated fatty sources, such as seafood, olive oil, and plenty of fruits and vegetables, but less dairy than the typical American diet. The Mediterranean diet has been associated with positive health outcomes.
Healthy Vegetarian Eating PatternA vegetarian diet differs from other diets primarily by restricting foods of animal origin, such as meats, poultry, fish, eggs, and dairy products (U.S. Department of Health and Human Services and U.S. Department of Agriculture 2015). People choose vegetarian diets for various reasons, including health benefits, religious beliefs, ethical considerations, or environmental concerns. These diets are generally lower in calories, saturated fats, and cholesterol while higher in legumes, soy products, nuts and seeds, whole grains, fruits, vegetables, and fiber.
There are several types of vegetarian diets. Some individuals may consume only plant-based foods (vegans), while others include dairy products (lacto vegetarians). A third group includes dairy products and eggs (lacto-ovo vegetarians), and a fourth group adds fish or seafood to their diet (pescatarians). Some people may occasionally stray from their diet during special social events due to circumstances such as travel or for the sake of variety (partial or semi-vegetarian).
Depending on the strictness of the vegetarian diet, individuals may face challenges in obtaining a nutritionally adequate intake, particularly concerning protein, calcium, vitamin D, iron, and B vitamins, depending on whether they include dairy or eggs. In some cases, vitamin and mineral supplements may be necessary.
It’s advisable to consult with a registered dietitian nutritionist (RDN), especially for growing children and teenagers, pregnant and lactating women, or individuals with chronic health conditions (Melina, Craig, and Levin, 2016).
Food Safety Basics
Food allergies and intolerances concern some people, but food safety concerns everyone. The federal government provides excellent resources to help keep you safe about food practices. If they have ever suffered from food poisoning, you understand how sick you can get from contaminated food. They advocate these four simple steps for food safety.
- Frequently clean your hands and surfaces! Bacteria that cause illness can thrive in various kitchen areas and may spread even if you wash your hands, utensils, and surfaces properly.
- Keep raw meat, poultry, seafood, and eggs separate from ready-to-eat foods to prevent cross-contamination. This includes ensuring they are separated in your grocery cart and refrigerator.
- Cook food to the appropriate temperature! The danger zone for bacteria that cause food poisoning is between 40 and 140 degrees Fahrenheit (4 to 60 degrees Celsius). Bacteria can multiply rapidly, so knowing the proper temperatures for different foods and cooking methods is essential.
- Chill. Refrigerate promptly! Illness-causing bacteria can grow in foods within two hours, especially in a warm environment. Therefore, cooling foods promptly is critical. Place meat and dairy consistently excellent near the back of the fridge. See Figure 8.7 for tips on planning wisely and choosing carefully to keep you on the right path as you design your diet plan.
Summary
Maintaining a high-quality diet during college requires a fundamental understanding of your macronutrient needs (protein, carbohydrates, and fats), micronutrient needs (vitamins and minerals), fiber intake, and hydration requirements. While many think of diet in terms of calories or energy intake, a nutritious diet can significantly impact your academic and social performance and help prevent chronic diseases later in life. Government agencies and scientific organizations provide guidelines and resources to help you plan a healthy diet. It is essential to become an informed consumer who can identify high-quality foods, supplements, and resources to maintain your health.