WEEK 2 CARBOHYDRATES
Carbohydrate is NOT a dirty word!! In fact, healthy carbs should make up most of your daily calories because this macro provides your body (and brain) with energy.
· 4 calories per gram
· 45-65% of daily calories (225 - 325 grams daily)
· Body’s main fuel source (blood glucose)
· Includes: sugar, starch, fiber
· Complex carb (slow digestion) includes starch and fiber: vegetables, grains, legumes
· Simple carb (quick digestion) include sugar: sucrose (table sugar), fructose (fruit sugar), lactose (milk sugar)
· Sugar has 16 calories per teaspoon
· Limit added sugar to 6 teaspoons daily (American Heart Association)
Foods high in carbohydrates are an important part of a healthy diet. Carbohydrates provide the body with glucose, which is converted to energy used to support bodily functions and physical activity. But carbohydrate quality is important; some types of carbohydrate-rich foods are better than others:
· The healthiest sources of carbohydrates—unprocessed or minimally processed whole grains, vegetables, fruits and beans—promote good health by delivering vitamins, minerals, fiber, and a host of important phytonutrients.
· Unhealthier sources of carbohydrates include white bread, pastries, sodas, and other highly processed or refined foods. These items contain easily digested carbohydrates that may contribute to weight gain, interfere with weight loss, and promote diabetes and heart disease.
Carbohydrates are a type of macronutrient found in many foods and beverages. Most carbs occur naturally in plant-based foods, such as grains. Food manufacturers also add carbs to processed foods in the form of starch or added sugar.
Common sources of naturally occurring carbohydrates include:
· Beans, peas and lentils
Types of carbohydrates
There are three main types of carbohydrates:
· Sugar. Sugar is the simplest form of carbohydrate. It occurs naturally in some foods, including fruits, vegetables, milk and milk products. Types of sugar include fruit sugar (fructose), table sugar (sucrose) and milk sugar (lactose). Added sugars can be found in many foods, such as cookies, sugary drinks and candy.
· Starch. Starch is a complex carbohydrate. This means it is made of many sugar units bonded together. Starch occurs naturally in vegetables, grains, and cooked dry beans and peas.
· Fiber. Fiber also is a complex carbohydrate. It occurs naturally in fruits, vegetables, whole grains, and cooked dry beans and peas.
More carbohydrate terms: Net carbs and glycemic index
The terms "low carb" or "net carbs" often appear on product labels. Typically, the term "net carbs" means total carbs minus fiber (which is undigested and excreted by the body) and/or sugar alcohols (ingredients used as sweeteners and bulking agents, occur naturally from plant such as fruits and berries).
You probably have also heard talk about the glycemic index. The glycemic index classifies carbohydrate-containing foods according to their potential to raise blood sugar levels.
Weight-loss diets based on the glycemic index typically suggest limiting foods that are higher on the glycemic index. Foods with a relatively high glycemic index ranking include potatoes, white bread, and snack foods and desserts that have refined flours.
Many healthy foods are naturally lower on the glycemic index, like whole grains, legumes, vegetables, fruits and low-fat dairy products.
Carbohydrates and your health
Despite their bad reputation, carbohydrates are vital to your health for many reasons.
· Providing energy - Carbohydrates are the body's main fuel source. During digestion, sugars and starches are broken down into simple sugars and then absorbed into the bloodstream, where they're known as blood sugar (blood glucose). From there, glucose enters the body's cells with the help of insulin. Glucose is used by the body for energy. Glucose fuels your activities — whether it's going for a jog or simply breathing and thinking. Extra glucose is stored in the liver, muscles and other cells for later use…or extra glucose is converted to fat.
· Protecting against disease - Some evidence suggests that whole grains and dietary fiber from whole foods help lower your risk of heart disease and stroke. Fiber may also protect against obesity, colon and rectal cancers, and type 2 diabetes. Fiber is also essential for optimal digestive health.
· Controlling weight - Evidence shows that eating plenty of fruit, vegetables and whole grains can help you control your weight. Their bulk and fiber content aids weight control by helping you feel full on fewer calories. Despite what proponents of low-carb diets claim, few studies show that a diet rich in healthy carbs leads to weight gain or obesity.
Choose your carbohydrates wisely
Not all carbs are equally good for you. Here's how to make healthy carbohydrates work in a balanced diet:
· Focus on eating fiber-rich fruits and vegetables. Aim for whole fresh, frozen and canned fruits and vegetables without added sugar. Or have measured portions of fruit juices and dried fruits, which are concentrated sources of natural sugar, but have more calories. Whole fruits and vegetables have many health benefits. They add fiber, water and bulk, which help you feel fuller on fewer calories.
· Choose whole grains. Whole grains are better sources than refined grains of fiber and other important nutrients, such as B vitamins. Refined grains go through a process that strips out parts of the grain — along with some of the nutrients and fiber.
· Stick to low-fat dairy products. Milk, cheese, yogurt and other dairy products are good sources of calcium, protein, vitamin D, potassium, and other vitamins and minerals. Consider the low-fat versions to help limit calories and saturated fat; watch out for dairy products that have added sugar.
· Eat more beans, peas and lentils. Beans, peas and lentils are among the most versatile and nutritious foods. They are typically low in fat and high in folate, potassium, iron and magnesium. And they have useful fats and fiber. They are a good source of protein and can be a healthy substitute for meat, which has more saturated fat and cholesterol.
· Limit added sugars. Added sugar probably isn't harmful in small amounts. But there's no health benefit to having any amount of added sugar, such as in cookies and pastries. The Dietary Guidelines for Americans recommend that less than 10% of calories you eat or drink every day come from added sugar. Eating or drinking too many foods with sugar can also cause you to take in more than the calories you need each day.
CARBS & EXERCISE
Again, carbohydrates get broken down into glucose (blood sugar) in the digestive tract. Glucose then travels through the bloodstream and moves into cells, where it can be used for energy immediately or stored in our muscles and liver as glycogen, a form of sugar that can be used for fuel in the future.
When you exercise, carbs provide fuel for your workouts.
If you exercise without eating carbs first — and you tend not to have enough of these macronutrients in your diet to have a substantial reserve of glycogen in your muscles —your body breaks down protein in your muscles for fuel instead. Tapping these protein stores can make you fatigue more easily and more prone to dizziness and dehydration during intense workouts.
Simple carbs are sugars that get broken down quickly in the body, rapidly sending glucose into the bloodstream.
Sugar comes in two types: natural and added. Sources of natural sugar include fresh fruit and milk, while added sugar often resides in processed foods and drinks like packaged sweets, soda, and fruit juice.
This type of carb can cause a rapid spike in energy, followed by a feeling of fatigue.
While most registered dietitians will advise that you avoid simple carbs in your everyday diet, these foods may come in handy before a vigorous workout. If you snack before a workout, particularly in the morning, simple carbs are best to give you rapidly available fuel.
Decades of research have linked pre-workout simple carbs to benefits like better endurance. For example, a previous study found experienced cyclists doing exercise tests fatigued after 134 minutes without pre-workout carbs but lasted 157 minutes with a pre-workout drink of simple carbs. Another study also looked at cyclists and found they burned less glycogen in their muscles during workouts when they had simple carbs before exercise, and that they could exercise for longer before they fatigued compared with those participants who did not have simple carbs before exercise.
Drinks or smoothies with 300 to 400 calories are best within 60 minutes of your workout because they’re easily digested.
When opting for simple carbs, choose natural sources, such as fruit or milk with redeeming nutritional qualities versus added sources, like soda or candy. Remember, women should limit their intake of added sugar to 6 teaspoons daily.
Complex carbs are fiber and starches, and they have a role in boosting exercise performance, too. Compared with simple carbs, these take longer to break down into the body, creating more stable blood sugar levels.
Eating more whole grains can help boost stores of protein in our muscles and preserve muscle mass. A study compared the effect of a diet with lots of whole grains to a diet with lots of processed grains like white bread and found people who ate whole grains performed better on walking speed tests, had higher stores of protein in their muscles, and had better overall muscle function than people who did not eat these healthy foods.
There’s an easy way to tell whether your workout is intense enough to require extra carbs at the start, called the “talk test.” If you can easily talk in complete sentences while working out, this is probably a low-intensity exercise. During a moderate-intensity workout, you will only be able to string together a few words before you need a deep breath. And if talking at all is a challenge, your workout is intense.
For a low- or moderate-intensity workout of less than 60 minutes, you don’t need carbs beforehand.
The sugar and starch content of ripe vs. unripe fruit differs greatly
Once a fruit or vegetable reaches its full size, the ripening process begins. So, what exactly is happening at this point? Starch is being converted to sugar, pigments (also known as phenolic compounds) develop, and texture begins to soften as pectin converts from water-insoluble to soluble. All of this results in the mature, sweet, and flavor-filled produce we know and love.
At the start of this process, the levels of resistant starch in a piece of produce are high and are reduced as starches are converted. Resistant starch cannot be digested or broken down by enzymes in the mouth, stomach, or small intestine, so it passes into the large intestine to be fermented by gut microbiota. Resistant starch is essentially the 'food' the microbes in our gut need to survive.
When a simple sugar is consumed on its own, it is easily broken down. It passes quickly into the bloodstream, resulting in an all-too-familiar blood sugar spike and drop roller coaster and quick reappearance of hunger. Alternatively, when those same sugars are consumed in conjunction with resistant starch and/or fiber, the nutrients pass more slowly through the digestive tract, resulting in a more gradual release of glucose—aka sugar—into the bloodstream and increased satiety, or feelings of fullness.A benefit of slower absorption is that since the food is passing more slowly through the digestive tract, the body is able to pull out even more vitamins and nutrients, giving you more nutritional bang for your buck.
An unripe bananas (also known as green bananas) are higher in resistant starch and lower in sugar. When that banana ripens, the resistant starch gets converted into sugar, flipping the ratio. Consuming an unripe banana will result in a slower, more regulated release of sugar into the bloodstream, whereas consuming a ripe banana will cause blood sugar to spike more quickly. But remember, even ripest banana would lead to a far more gradual blood sugar spike than candy or soda due to the fiber that remains in the ripe version of the fruit.
One thing to look out for when eating raw bananas (and other foods high in resistant starches, such as raw potatoes and beans) are potential digestive woes. Since resistant starch travels all the way to your large intestine before it can be digested, it is possible that if your system is not used to consuming that type of starch and amount of fiber. If you have a sensitive stomach, start slowly and allow your system to adjust if you experience discomfort. Try gradually adding in more fiber and foods filled with resistant starch to get the ultimate health payoff, sans indigestion.
Antioxidant values typically increase as fruits ripen.
While the conversion of starch to sugar is the most notable change during the ripening process, vitamins, minerals, and antioxidants also develop and convert as fruit ripens. Antioxidants in particular have been shown to increase during the ripening process. Anthocyanin, which is the antioxidant compound that gives fruit and vegetables their deep purple color, has been shown to increase more than fourfold in studies of blackberries as they transition from underripe to ripe.
Luckily, we tend to be drawn to antioxidant-rich fruits when they are at their peak ripeness (and therefore sweetness), so you are likely already reaping this health benefit without much effort beyond your normal enjoyment of nature’s candy.
Vitamin C content increases or decreases, depending on the type of produce.
Vitamin C has also been shown to increase in bell peppers, tomatoes, and pineapple as ripening occurs. In oranges, grapes, and lemons however, vitamin C content is actually at its highest when the fruit is half ripe. Vitamin C can help support a healthy immune system, protect against free radicals, help speed up the body’s natural healing process, and even assist with the ability to absorb iron effectively.
SUGAR BY ANY OTHER NAME
Sugar (sucrose) comes from sugar beets and sugar cane. It is the generic name for sweet-tasting, soluble carbohydrates, many of which are used in food. Simple sugars, also called monosaccharides, include glucose, fructose, and galactose
Added sugar contributes calories but not nutrients. Too much added sugar can lead to health problems including high blood sugar, insulin resistance, metabolic syndrome, dental issues such as cavities, increased triglycerides, obesity and type 2 diabetes.
All sugar, whether natural or processed, is a type of simple carbohydrate your body uses for energy. Fruits, vegetables and dairy foods naturally contain sugar.
"Added sugars" are the sugars and syrups added to foods during processing. Sodas, desserts, and energy and sports drinks are the top sources of added sugars for most people in the U.S. But these aren't the only foods with added sugars.
Adding sugar to processed foods makes them more appealing. Sugar is also added to foods because it:
· Gives baked goods flavor, texture and color
· Helps preserve foods, such as jams and jellies
· Fuels fermentation, which enables bread to rise
· Serves as a bulking agent in baked goods and ice cream
· Balances the acidity of foods containing vinegar and tomatoes
Read the INGREDIENTS list! Packaged foods and drinks must list ingredients in descending order by weight. If sugar is one of the first few ingredients, the product is likely to be high in added sugars.
Sugar goes by many names, depending on its source and how it was made. This can make it hard to identify added sugars, even when you read ingredient lists and food labels.
Check for ingredients ending in "ose" — that's the chemical name for many types of sugar, such as fructose, glucose, maltose and dextrose.
Here's a list of other common types of added sugars:
· Cane juice and cane syrup
· Corn sweetener and high-fructose corn syrup
· Fruit juice concentrate and nectar
· Maple syrup
Despite what you may have heard, there's no nutritional advantage to honey, brown sugar or other types of sugar over white sugar.
To reduce the added sugars in your diet, try these tips:
· Drink water, other calorie-free drinks or low-fat milk instead of sugary sodas or sports drinks. That goes for coffee drinks, too.
· When you drink fruit juice, make sure it's 100% fruit juice — not juice drinks that have added sugars. Better yet, eat the fruit rather than drink the juice to get the fiber as well.
· Choose breakfast cereals with less sugar. Skip sugary and frosted cereals.
· Opt for reduced-sugar varieties of syrups, jams, jellies and preserves.
· Choose fresh fruit for dessert instead of cakes, cookies, pies, ice cream and other sweets.
· Buy canned fruit packed in water or juice, not syrup. If you do purchase fruit packed in syrup, drain and rinse it with water to remove excess syrup.
· Choose nutrient-rich snacks such as vegetables, fruits, low-fat cheese, whole-grain crackers and low-fat, low-calorie yogurt instead of candy, pastries and cookies.
What are sugar substitutes?
Sugar substitutes taste sweet but don’t contain sugar. They have fewer calories than sugar, and some have no calories at all. Foods labeled “sugar-free,” “keto,” “low carb” or “diet” often contain sugar substitutes, which fall into three categories: artificial sweeteners, sugar alcohols and novel sweeteners.
Most artificial sweeteners (also called nonnutritive sweeteners) are created from chemicals in a lab. A few are made from natural substances like herbs. They can be 200 to 700 times sweeter than table sugar.
These sweeteners don’t contain calories or sugar, but they also don’t have beneficial nutrients like vitamins, fiber, minerals or antioxidants. They are regulated by the U.S. Food and Drug Administration (FDA) as food additives.
Some experts believe that artificial sweeteners pose health hazards, from weight gain to cancer. But research on this is ongoing, and past studies showing health risks were conducted on animals, not humans. Studies on people have shown these products to be generally safe if more than the acceptable daily intake for each is not consumed.
The FDA has approved several artificial sweeteners:
Acesulfame potassium (Ace-K)
Similar to artificial sweeteners, sugar alcohols are created synthetically (typically from sugars themselves). Sugar alcohols are used in many processed foods. They’re not as sweet as artificial sweeteners, and they add texture and taste to foods like chewing gum and hard candies. They can cause gastrointestinal irritation like bloating, gas or diarrhea in some people.
Unlike other sugar substitutes, sugar alcohols must be listed on nutrition facts labels. Examples include:
Novel sweeteners are derived from natural sources. This relatively new group, sometimes called “plant-derived noncaloric sweeteners,” provides many of the benefits of both artificial and natural sweeteners like fruit or honey. Novel sweeteners are not a significant source of calories or sugar, so they don’t lead to weight gain or blood sugar spikes. They are also typically less processed and are more similar to their natural sources compared to artificial sweeteners.
Removing all sugar from your diet means you might miss important nutrients found in fruits, whole grains and dairy. Diets that cut out all carbohydrates and sugars, such as the ketogenic diet, can be harmful to your health.
Without sugar, our bodies must find alternative sources of energy. So, they use ketone bodies (substances produced by the liver) for fuel ― basically, the body goes into starvation mode. A diet without any carbohydrates or sugars may cause “keto flu,” with symptoms such as headache, fatigue and brain fog.
Dietitians recommend cutting way back on highly refined foods and beverages with added sugars and artificial sweeteners, but not removing all carbohydrates from your diet.