During the 1970s some investigators proposed that refined carbohydrates, especially sugar and a low intake of dietary fiber, were major factors in coronary heart disease (CHD). This suggestion was eclipsed by the belief that an excess intake of saturated fatty acids (SFA) was the key dietary factor, a view that prevailed from roughly 1974 to 2014. Findings that have accumulated since 1990 inform us that the role of SFA in the causation of CHD has been much exaggerated. A switch from SFA to refined carbohydrates does not lower the ratio of total cholesterol to HDL-cholesterol in the blood and therefore does not prevent CHD. A reduced intake of SFA combined with an increased intake of polyunsaturated fatty acids lowers the ratio of total cholesterol to HDL-cholesterol; this may reduce the risk of CHD. The evidence linking carbohydrate-rich foods with CHD has been steadily strengthening. Refined carbohydrates, especially sugar-sweetened beverages, increase the risk of CHD. Conversely, whole grains and cereal fiber are protective. (11)
What is SUGAR
Carbohydrates, or carbs, are a type of nutrient in foods. The three basic forms are sugars, starches and fiber. When you eat or drink something with carbs, your body breaks down the sugars and starches into a type of sugar called glucose, the main source of energy for cells in your body. Fiber passes through your body undigested. Two main hormones from your pancreas help regulate glucose in your bloodstream. The hormone insulin moves glucose from your blood into your cells. The hormone glucagon helps release glucose stored in your liver when your blood sugar (blood glucose) level is low. This process helps keep your body fueled and ensures a natural balance in blood glucose. Different types of carbohydrate foods have properties that affect how quickly your body digests them and how quickly glucose enters your bloodstream.
It is a number that gives you an idea about how fast your body converts the carbs in a food into glucose. Two foods with the same amount of carbohydrates can have different glycemic index numbers.
The smaller the number, the less impact the food has on your blood sugar.
- 55 or less = Low (good)
- 56- 69 = Medium
- 70 or higher = High (bad).
Comparing these values, therefore, can help guide healthier food choices. For example, an English muffin made with white wheat flour has a GI value of 77. A whole-wheat English muffin has a GI value of 45.
One limitation of GI values is that they don’t reflect the likely quantity you would eat of a particular food.
For example, watermelon has a GI value of 80, which would put it in the category of food to avoid. But watermelon has relatively few digestible carbohydrates in a typical serving. In other words, you have to eat a lot of watermelon to significantly raise your blood glucose level.
Glycemic load (GL)
To address this problem, researchers have developed the idea of glycemic load (GL), a numerical value that indicates the change in blood glucose levels when you eat a typical serving of the food. For example, a 4.2-ounce (120-gram, or 3/4-cup) serving of watermelon has a GL value of 5, which would identify it as a healthy food choice. For comparison, a 2.8-ounce (80-gram, or 2/3-cup) serving of raw carrots has a GL value of 2.
Sydney University’s table of GI values also includes GL values. The values are generally grouped in the following manner:
- Low GL: 1 to 10
- Medium GL: 11 to 19
- High GL: 20 or more
The glycemic index should not be used in isolation” and that other nutritional factors — calories, fat, fiber, vitamins and other nutrients — should be considered. (1)
Foods that are close to how they’re found in nature tend to have a lower glycemic index than refined and processed foods.
Glycemic Index Can Change
That number is a starting point on paper. It could be different on your plate, depending on several things.
Preparation. Fat, fiber, and acid (such as lemon juice or vinegar) lower the glycemic index. The longer you cook starches like pasta, the higher their glycemic index will be.
Ripeness. The glycemic index of fruits like bananas goes up as they ripen.
Other foods eaten at the same time. Bring down the overall glycemic index of a meal by combining a high-glycemic index food with foods that have lower ones. (2)
Natural sugar and refined sugar
Sugar, in all forms, is a simple carbohydrate that the body converts into glucose and uses for energy. But the effect on the body and your overall health depends on the type of sugar you’re eating, either natural or refined.
Natural sugars are found in fruit as fructose and in dairy products, such as milk and cheese, as lactose. Foods with natural sugar have an important role in the diet of cancer patients and anyone trying to prevent cancer because they provide essential nutrients that keep the body healthy and help prevent disease.
Refined sugar comes from sugar cane or sugar beets, which are processed to extract the sugar. It is typically found as sucrose, which is the combination of glucose and fructose. We use white and brown sugars to sweeten cakes and cookies, coffee, cereal and even fruit. Food manufacturers add chemically produced sugar, typically high-fructose corn syrup, to foods and beverages, including crackers, flavored yogurt, tomato sauce and salad dressing. Low-fat foods are the worst offenders, as manufacturers use sugar to add flavor.
Most of the processed foods we eat add calories and sugar with little nutritional value.
In contrast, fruit and unsweetened milk have vitamins and minerals. Milk also has protein and fruit has fiber, both of which keep you feeling full longer.
How the body metabolizes the sugar in fruit and milk differs from how it metabolizes the refined sugar added to processed foods. The body breaks down refined sugar rapidly, causing insulin and blood sugar levels to skyrocket. Because refined sugar is digested quickly, you don’t feel full after you’re done eating, no matter how many calories you consumed. The fiber in fruit slows down metabolism, as fruit in the gut expands to make you feel full.
But there’s a caveat. Once the sugar passes through the stomach and reaches the small intestine, it doesn’t matter if it came from an apple or a soft drink.
How much sugar is already in your blood will determine how the body uses the sugar. If you already have a lot of sugar in your system, then what you just digested will form either fat or glycogen, the storage form of glucose that’s used for quick energy. It doesn’t matter if it’s junk food or fruit. (5)
SUGAR AND ILLNESSES
Consumption of added sugar is associated with development and/or prevalence of fatty liver, dyslipidemia, insulin resistance, hyperuricemia, CVD and T2DM, often independent of body weight gain or total energy intake. Functional magnetic resonance imaging (fMRI) of the brain demonstrates that the brain responds differently to fructose or fructose-containing sugars compared with glucose or aspartame. (6)
Most meta-analyses have shown that the risk of obesity, diabetes, cardiovascular disease, and metabolic syndrome are related to consumption of beverages sweetened with sugar or high-fructose corn syrup. Calorically sweetened beverage intake has also been related to the risk of non-alcoholic fatty liver disease, and, in men, gout. Several randomized trials of sugar-containing soft drinks versus low-calorie or calorie-free beverages show that either sugar, 50% of which is fructose, or fructose alone increases triglycerides, body weight, visceral adipose tissue, muscle fat, and liver fat. Fructose is metabolized primarily in the liver. When it is taken up by the liver, ATP decreases rapidly as the phosphate is transferred to fructose in a form that makes it easy to convert to lipid precursors. Fructose intake enhances lipogenesis and the production of uric acid. By worsening blood lipids, contributing to obesity, diabetes, fatty liver, and gout, fructose in the amounts currently consumed is hazardous to the health of some people. (7)
The grapefruit diet. Atkins. South Beach. Low-fat. Low-carb. High-protein. It seems like there’s a fad diet for every taste. But there’s one ingredient just about all of them agree should be cut: added sugars. That’s because excess sugars are not just empty calories; they also contribute to weight gain, which may in turn lead to obesity. With obesity linked to 13 types of cancer, watching your waistline is important for your health, not just your wardrobe. one of the easiest ways to improve your diet is to cut back on added sugars—not naturally occurring sugars like fruits, vegetables and lactose in milk products, but the sugars and syrups that are added to foods during processing or preparation, including those you sprinkle on at the dinner table. These high-calorie sweeteners can be found in a variety of foods and beverages, including sodas, juices, sports drinks, bake goods, cereals, yogurts, coffee creamers—even granola, fruit snacks and salad dressing.
The American Heart Association recommends no more than 25 grams of added sugars per day for women and 38 grams for men. To put that into perspective, one teaspoon equals four grams of sugar, so no more than six teaspoons of sugar a day, if you’re a woman, or more than nine if you’re a man. And yet, the average American consumes 89 grams of added sugars per day—two to three times the recommended amount.
One way to cut back on sugars, Lammersfeld says, is by following the SLASH plan:
Stay in for meals: Gain control by cooking at home and packing lunch and snacks.
Look at labels: Identify the difference between naturally occurring and added sugars on nutrition labels.
Alternate sugar sources: Use or make your own condiments and sauces without added sugar.
Sweeten yourself: Buy unsweetened products and sweeten them yourself to use less of any alternative sweetener.
Hydrate: Rethink what you are drinking and choose water more often.
Besides cutting added sugars, Lammersfeld says there are lots of changes you can make to give your diet a healthy makeover, including looking at existing labels for clues (sugar, honey, dextrose, etc.) that sugar has been added. She offered these additional tips:
- Eat generous amounts of foods that do not come in labels. These are the natural products, like fruits, vegetables, nuts and grains.
- Limit the amount of foods that have labels, especially the processed and prepackaged variety.
- Get between 21 to 38 grams of fiber each day.
- Try to consume to one to three servings of fermented foods and beverages daily, such as yogurt, kefir and miso.
- Eat two servings of fish twice a week or a substitute such as ground flax seed. (4)
We eat more refined sugar today than our parents and grandparents did three decades ago, which has resulted in increasing obesity rates among adults and children. Obesity has been associated with certain cancers, including breast, prostate, uterine, colorectal and pancreatic. On the flip side, fruits high in antioxidants—blueberries, blackberries, raspberries, strawberries and apples—may reduce your cancer risk. The fiber in fruit, found mainly in its skin, suppresses your appetite to prevent overeating and weight gain.
Our clinical oncology dietitians recommend eating whole foods that are low in refined sugars. Whole foods refer to foods that are either unprocessed, such as fruit and vegetables, or minimally processed, such as whole grains.
The big picture is being a healthy weight and making healthy food choices. It’s about eating a diet with whole foods, lean proteins, complex carbohydrates like quinoa rather than white bread, and non-starchy vegetables. Focus on making good food choices every day on a consistent basis, not on the one piece of cake you had as a treat. (5)
Sugar and different names: where?
Added sugars can be hard to spot on nutrition labels since they can be listed under a number of names, such as corn syrup, agave nectar, palm sugar, cane juice, molasses, saccharose, honey, cane sugar, grape sugar, muscovado, mannose, brown sugar , golden syrup, maple syrup, coconut sugar, or sucrose.
No matter what it’s called, sugar is sugar, and it can negatively affect your body in many ways. Here’s a closer look at how sugar can mess with your health, from head to toe.
Glucose or Fructose?
Fructose and glucose in soft drinks and fruit drinks account for just under 50 % of added sugars. Soft drinks intake has risen five-fold between 1950 and 2000, and this increase in intake of simple sugars has raised health concerns. The risks of cardiovascular disease, some cancer, obesity and the metabolic syndrome have all been related to consumption of sugar-sweetened beverages in several, but not all meta-analyses. Fructose and sugar-sweetened beverages have also been related to the risk of gout in men, and to non-alcoholic fatty liver disease. Studies show that the calories in sugar-sweetened beverages do not produce an adequate reduction in the intake of other foods, leading to increased caloric intake. Plasma triglycerides are increased by sugar-sweetened beverages, and this increase appears to be due to fructose, rather than to glucose in sugar. Several 10-week to 26-week randomized trials of sugar-containing soft drinks show increases in triglycerides, body weight, and visceral adipose tissue; there were also increases in muscle fat and liver fat, which might lead to non-alcoholic-fatty liver disease. (8)
Many of the controversies related to fructose related sugars are based on the well-known differences between metabolism of fructose and glucose in the liver.
Over 90% of fructose ingested is absorbed through the small intestine and metabolized in the liver on first pass. In contrast, glucose is metabolized by a variety of organs. It is important to note, however, that the pathways are interactive. Numerous studies including isotope studies have shown that roughly 50% of fructose is converted to glucose within the liver. An additional 15%–20% is converted to glycogen, 20%–25% to lactate, and a few percent to carbon dioxide.
Multiple studies have shown that only 1%–5% of consumed fructose may follow the pathway of de novo lipogenesis and be converted into free fatty acids which are then packaged as triglycerides and either stored in the liver or released in the bloodstream. Some short-term data with very large doses of pure fructose have suggested that increases in liver fat can be achieved over a short period of time; Faeh et al. gave seven healthy men six days of a high fructose diet comprising an extra 25% of total calories and demonstrated suppression of adipose tissue lipolysis. Schwarz et al. utilizing a diet with 25% pure fructose demonstrated increased liver fat.
Effects of Sugars on Body Weight and Body Composition
Dietary sugars may have differential effects on blood lipids. A number of studies have demonstrated that diets containing greater than 20% of kcal from simple sugars may result in elevated fasting triglycerides which is a known risk factor for CVD.
The American Heart Association Scientific Statement on triglycerides lists avoiding excess fructose as one mechanism for decreasing the risk of hypertriglyceridemia.
Several recent systematic reviews and meta-analyses, however, have reported that in trials where fructose is substituted isocalorically for other carbohydrates it does not result in increased fasting triglycerides or post-prandial triglycerides. (9)
When the high-fructose diet was associated with exercise, all the effects of fructose on lipoprotein metabolism were totally prevented. Exercise-enhanced lipoprotein lipase activity facilitates the disposal of lipids in adipose cells or skeletal muscle fibers.
Even with such a high intake, exercise completely prevented fructose-induced alterations of lipid metabolism.
SUGAR and DEPRESSION
Intake of sweet food, beverages and added sugars has been linked with depressive symptoms in several populations. Aim of this study was to investigate systematically cross-sectional and prospective associations between sweet food/beverage intake, common mental disorder (CMD) and depression and to examine the role of reverse causation (influence of mood on intake) as potential explanation for the observed linkage.
There are several plausible biological explanations for an association of habitual sugar intake and subsequent risk of depression, in the long-term.
Firstly, low levels of the growth factor brain derived neurotrophic factor (BDNF) have been discussed as facilitating neurogenesis and hippocampal atrophy in depression.
Secondly, carbohydrate consumption has been associated with increased circulating inflammatory markers, which may depress mood.
Thirdly, high sugar diets could induce hypoglycaemia through an exaggerated insulin response and thereby influence hormone levels and potentially mood states.
Fourthly, addiction-like effects of sugar suggest dopaminergic neurotransmission mechanisms might connect frequent sugar intake with depression.
Lastly, obesity could be a mediating factor between a sugar-dense diet and depression not only via inflammatory but also psychosocial factors like weight discrimination.
With a high prevalence of mood disorders, and sugar intake commonly two to three times the level recommended, our findings indicate that policies promoting the reduction of sugar intake could additionally support primary and secondary prevention of depression. (10)
Eating sugar gives your brain a huge surge of a feel-good chemical called dopamine, which explains why you’re more likely to crave a candy bar at 3 p.m. than an apple or a carrot. Because whole foods like fruits and veggies don’t cause the brain to release as much dopamine, your brain starts to need more and more sugar to get that same feeling of pleasure. This causes those “gotta-have-it” feelings for your after-dinner ice cream that are so hard to tame.
The occasional candy or cookie can give you a quick burst of energy (or “sugar high”) by raising your blood sugar levels fast. When your levels drop as your cells absorb the sugar, you may feel jittery and anxious. But if you’re reaching into the candy jar too often, sugar starts to have an effect on your mood beyond that 3 p.m. slump.
You probably rolled your eyes at age 12, but your mother was right: Candy can rot your teeth. Bacteria that cause cavities love to eat sugar lingering in your mouth after you eat something sweet.
If you have joint pain, here’s more reason to lay off the candy: Eating lots of sweets has been shown to worsen joint pain because of the inflammation they cause in the body. Plus, studies show that sugar consumption can increase your risk of developing rheumatoid arthritis.
Another side effect of inflammation: It may make your skin age faster. Sugar attaches to proteins in your bloodstream and creates harmful molecules called “AGEs,” or advanced glycation end products. These molecules do exactly what they sound like they do: age your skin. They have been shown to damage collagen and elastin in your skin — protein fibers that keep your skin firm and youthful. The result? Wrinkles and saggy skin.
An abundance of added sugar may cause your liver to become resistant to insulin. This means your body isn’t able to control your blood sugar levels as well, which can lead to type 2 diabetes.
When you eat excess sugar, the extra insulin in your bloodstream can affect your arteries, part of your body’s circulatory system. It causes their walls to grow faster than normal and get tense, which adds stress to your heart and damages it over time. This can lead to heart disease, heart attacks, and strokes. Research also suggests that eating less sugar can help lower blood pressure, a major risk factor for heart disease. Plus, people who eat a lot of added sugar (where at least 25% of their calories comes from added sugar) are twice as likely to die of heart disease as those whose diets include less than 10% of total calories from added sugar.
When you eat, your pancreas pumps out insulin. But if you’re eating way too much sugar and your body stops responding properly to insulin, your pancreas starts pumping out even more insulin. Eventually, your overworked pancreas will break down and your blood sugar levels will rise, setting you up for type 2 diabetes and heart disease.
If you have diabetes, too much sugar can lead to kidney damage. The kidneys play an important role in filtering your blood sugar. Once blood sugar levels reach a certain amount, the kidneys start to let excess sugar into your urine. If left uncontrolled, diabetes can damage the kidneys, which prevents them from doing their job in filtering out waste in your blood. This can lead to kidney failure.
Your Body Weight
This probably isn’t news to you, but the more sugar you eat, the more you’ll weigh. Research shows that people who drink sugar-sweetened beverages tend to weigh more — and be at higher risk for type 2 diabetes — than those who don’t. One study even found that people who increased their sugar intake gained about 1.7 pounds (800 g) in less than 2 months.
Your Sexual Health
One common side effect of chronically high levels of sugar in the bloodstream is that it can make men impotent.
Behaviors to be adopted
A trendy sugar detox diet promises to end your craving for sweets and help you lose weight.
Some signs that you are eating too much sugar: You crave sugar, lose control, and eat more than you planned.
Sugar fuels every cell in the brain. Your brain also sees sugar as a reward, which makes you keep wanting more of it. If you often eat a lot of sugar, you’re reinforcing that reward, which can make it tough to break the habit.
Why do you get a rush when you eat a midday candy bar? The sugar in it — called a simple carbohydrate — is quickly turned into glucose in your bloodstream. Your blood sugar levels spike. Simple carbs are also found in fruits, veggies, and dairy products. But these have fiber and protein that slow the process. Syrup, soda, candy, and table sugar don’t.
Your body needs to move glucose out of the bloodstream and into your cells for energy. To do this, your pancreas makes insulin, a hormone. As a result, your blood sugar level may have a sudden drop. This rapid change in blood sugar leaves you feeling wiped out and shaky and searching for more sweets to regain that sugar “high.” So that midday sugary treat has set you up for more bad eating.
Starch Can Equal Sugar
Think you don’t have a sweet tooth, but crave bagels, chips, or french fries? These starchy foods are complex carbs that the body breaks down into simple sugars. Eaten without better foods, starches can make blood sugar surge and crash like sugar. White rice and white flour do this. Highly refined starches like white bread, pretzels, crackers, and pasta are worst.
Retrain Your Taste Buds
You don’t need sugar as much as you think you do. In fact, you can train your taste buds to enjoy things that aren’t as sweet. Try cutting out one sweet food from your diet each week. For example, pass on dessert after dinner. Start putting less sugar in your coffee or cereal. Over time, you will lose your need for that sugar taste.
Kick the Habit in Baby Steps
If you make small, simple changes to your diet, it’s easy to keep them up. Start by eating more fruits and vegetables. Drink extra water. Check food labels, and pick those that don’t have a lot of sugar. Cut out a little bit of sugar each week. After a few weeks, you’ll be surprised at how little you miss it.
Let Protein Help
Eating protein is an easy way to curb sugar cravings. High-protein foods digest more slowly, keeping you feeling full for longer. Protein doesn’t make your blood sugar spike the way refined carbs and sugars do. Pick proteins like lean chicken, low-fat yogurt, eggs, nuts, or beans.
Fill Up on Fiber
Fiber helps fight a sugar itch in many ways. First, it keeps you full. High-fiber foods also give you more energy. Because they don’t raise your blood sugar, there’s no hungry crash after. Choose fruits, vegetables, and whole grains. Or smear some peanut butter on an apple for a protein/fiber combo.
Exercise can help wipe out those sugar cravings and change the way you eat in general. You start to feel better and want healthier foods. Do what you like, such as walking, riding your bike, or swimming. Start out slow, and work toward at least 30 minutes at a time, 5 days a week.
Can Artificial Sweeteners Help?
Some studies suggest artificial sweeteners may leave you craving more sugar. That could make it harder to control your weight. The problem is, some experts say, that artificial sweeteners don’t help you break your taste for sweets. Pay attention to your body. Are sweeteners making you crave even more sugar? If so, look elsewhere for that sweet taste.
Limit the ‘Healthy’ Sugars, Too
Honey, brown sugar, and cane juice may sound healthy. But sugar is sugar. Whether it comes from bees or sugar cane, it can cause your blood sugar to rise. Honey and unrefined sugars are slightly higher in nutrients, but their calories still count.
If you’re like most people in the U.S., you eat 19 teaspoons or more of added sugar a day. That adds up to 285 calories, which health experts say is way too much. How much sugar should you be eating? According to the American heart Association, no more than 6 teaspoons daily for women. That’s about 100 calories. Men should get a max of 9 teaspoons. That’s about 150 calories.
Scout Out Hidden Sugar
Sugar can hide in foods where you least expect it. Although they don’t seem sweet, ketchup, barbecue sauce, and pasta sauce can have loads of sugar. So can reduced-fat salad dressings, bread, baked beans, and some flavored coffees. Get in the habit of reading labels. Filter out high-sugar foods before they hit your shopping cart.
Watch out the label for items that list any form of sugar in the first few ingredients, or have more than 4 total grams of sugar.
Does Sugar Cause Diabetes?
Sugar itself doesn’t cause diabetes. But lots of sugar splurges can point you there. Too much of anything, including sugar, can pack on pounds, for one thing. Heavy bodies may have a harder time using insulin, the hormone that controls blood sugar. When your body resists insulin, blood sugar and your risk of diabetes go up. (3)
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