Understanding Food Labels

Many people would like to know how to read food labels. This article will educate you on how to use the Nutrition Facts Label on foods so that you can make quick, informed food choices that contribute to a healthy diet.


OVERVIEW OF THE NUTRITION FACTS LABEL:


THE SERVING SIZE: [#1 on sample label]

The first place to start when you look at the Nutrition Facts label is the serving size and the number of servings in the package. Serving sizes are standardized to make it easier to compare similar foods. They are provided in familiar units, such as cups or pieces, followed by the metric amount, e.g., the number of grams.

The size of the serving on the food package influences the number of calories and all the nutrient amounts listed on the top part of the label. Pay attention to the serving size, especially how many servings there are in the food package. Then ask yourself, "How many servings am I consuming"? (e.g., 1/2 serving, 1 serving, or more) In the sample label, one serving of macaroni and cheese equals one cup. If you ate the whole package, you would eat two cups. That doubles the calories and other nutrient numbers, including the %Daily Values.

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CALORIES (and Calories From Fat): [#2 on sample label]

Calories provide a measure of how much energy you get from a serving of this food. Many Americans consume more calories than they need without meeting recommended intakes for a number of nutrients. The calorie section of the label can help you manage your weight (i.e., gain, lose, or maintain.)

Remember: The number of servings you consume determines the number of calories you actually eat (your portion amount).

In the example, there are 250 calories in one serving of this macaroni and cheese. How many calories from fat are there in ONE serving? Answer: 110 calories, which means almost half the calories in a single serving come from fat. What if you ate the whole package content? Then, you would consume two servings, or 500 calories, and 220 would come from fat.


General Guide to Calories:

40 Calories is low
100 Calories is moderate
400 Calories or more is high

The General Guide to Calories provides a general reference for calories when you look at a Nutrition Facts label. This guide is based on a 2,000 calorie diet.

Eating too many calories per day is linked to overweight and obesity.

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THE NUTRIENTS: HOW MUCH? [#3 and 4 on sample label]

Look at the top of the nutrient section in the sample label. It shows you some key nutrients that impact on your health and separates them into two main groups:


LIMIT THESE NUTRIENTS: [#3 on sample label]:

The nutrients listed first are the ones Americans generally eat in adequate amounts, or even too much. They are identified in yellow as "Limit these Nutrients". Eating too much fat, saturated fat, trans fat, cholesterol, or sodium may increase your risk of certain chronic diseases, like heart disease, some cancers, or high blood pressure.

Important: Health experts recommend that you keep your intake of saturated fat, trans fat and cholesterol as low as possible as part of a nutritionally balanced diet.


GET ENOUGH OF THESE: [#4 on sample label]:

Most Americans don't get enough dietary fiber, vitamin A, vitamin C, calcium, and iron in their diets. They are identified in blue as "Get Enough of these Nutrients". Eating enough of these nutrients can improve your health and help reduce the risk of some diseases and conditions. For example, getting enough calcium may reduce the risk of osteoporosis, a condition that results in brittle bones as one ages (see calcium section below). Eating a diet high in dietary fiber promotes healthy bowel function. Additionally, a diet rich in fruits, vegetables, and grain products that contain dietary fiber, particularly soluble fiber, and low in saturated fat and cholesterol may reduce the risk of heart disease.

Remember: You can use the Nutrition Facts label not only to help limit those nutrients you want to cut back on but also to increase those nutrients you need to consume in greater amounts.

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UNDERSTANDING THE FOOTNOTE ON THE BOTTOM OF THE NUTRITION FACTS LABEL: [#5 on sample label]:

Note the * used after the heading "%Daily Value" on the Nutrition Facts label. It refers to the Footnote in the lower part of the nutrition label, which tells you "%DVs are based on a 2,000 calorie diet". This statement must be on all food labels. But the remaining information in the full footnote may not be on the package if the size of the label is too small. When the full footnote does appear, it will always be the same. It doesn't change from product to product, because it shows recommended dietary advice for all Americans--it is not about a specific food product.

Look at the Daily Values (DV) for each nutrient listed. These are based on public health experts' advice. DVs are recommended levels of intakes. DVs in the footnote are based on a 2,000 or 2,500 calorie diet. Note how the DVs for some nutrients change, while others (for cholesterol and sodium) remain the same for both calorie amounts.

Now let's look at the %DVs (The Percent Daily Value):

The % Daily Values (%DVs) are based on the Daily Value recommendations for key nutrients but only for a 2,000 calorie daily diet--not 2,500 calories. You, like most people, may not know how many calories you consume in a day. But you can still use the %DV as a frame of reference whether or not you consume more or less than 2,000 calories.

The %DV helps you determine if a serving of food is high or low in a nutrient.

Note: a few nutrients, like trans fat, do not have a %DV--they will be discussed later.

Do you need to know how to calculate percentages to use the %DV? No, the label (the %DV) does the math for you. It helps you interpret the numbers (grams and milligrams) by putting them all on the same scale for the day (0-100%DV). The %DV column doesn't add up vertically to 100%. Instead each nutrient is based on 100% of the daily requirements for that nutrient (for a 2,000 calorie diet). This way you can tell high from low and know which nutrients contribute a lot, or a little, to your daily recommended allowance (upper or lower).

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QUICK GUIDE TO %DV: 5%DV or less is low and 20%DV or more is high [#6 on sample label]:

This guide tells you that 5%DV or less is low for all nutrients, those you want to limit (e.g., fat, saturated fat, cholesterol, and sodium), or for those that you want to consume in greater amounts (fiber, calcium, etc). As the Quick Guide shows, 20%DV or more is high for all nutrients.

Example: Look at the amount of Total Fat in one serving listed on the sample nutrition label. Is 18%DV contributing a lot or a little to your fat limit of 100% DV? Check the Quick Guide to %DV. 18%DV, which is below 20%DV, is not yet high, but what if you ate the whole package (two servings)? You would double that amount, eating 36% of your daily allowance for Total Fat. Coming from just one food, that amount leaves you with 64% of your fat allowance (100%-36%=64%) for all of the other foods you eat that day, snacks and drinks included.

Using The %DV For:

Comparisons: The %DV also makes it easy for you to make comparisons. You can compare one product or brand to a similar product. Just make sure the serving sizes are similar, especially the weight (e.g. gram, milligram, ounces) of each product. It's easy to see which foods are higher or lower in nutrients because the serving sizes are generally consistent for similar types of foods, except in a few cases like cereals.

Nutrient Content Claims: Use the %DV to help you quickly distinguish one claim from another, such as "reduced fat" vs. "light" or "nonfat." Just compare the %DVs for Total Fat in each food product to see which one is higher or lower in that nutrient--there is no need to memorize definitions. This works when comparing all nutrient content claims, e.g., less, light, low, free, more, high, etc.

Dietary Trade-Offs: You can use the %DV to help you make dietary trade-offs with other foods throughout the day. You don't have to give up a favorite food to eat a healthy diet. When a food you like is high in fat, balance it with foods that are low in fat at other times of the day. Also, pay attention to how much you eat so that the total amount of fat for the day stays below 100%DV.

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Nutrients With a %DV but No Weight Listed - Such as Calcium:

Calcium: Look at the %DV for calcium on food packages so you know how much one serving contributes to the total amount you need per day. Remember, a food with 20%DV or more contributes a lot of calcium to your daily total, while one with 5%DV or less contributes a little.

Experts advise adult consumers to consume adequate amounts of calcium, that is, 1,000mg or 100%DV in a daily 2,000 calorie diet. This advice is often given in milligrams (mg), but the Nutrition Facts label only lists a %DV for calcium.

For certain populations, they advise that adolescents, especially girls, consume 1,300mg (130%DV) and post-menopausal women consume 1,200mg (120%DV) of calcium daily. The DV for calcium on food labels is 1,000mg.

Don't be fooled -- always check the label for calcium because you can't make assumptions about the amount of calcium in specific food categories. Example: the amount of calcium in milk, whether skim or whole, is generally the same per serving, whereas the amount of calcium in the same size yogurt container (8oz) can vary from 20-45 %DV.


Equivalencies:
30% DV = 300mg calcium = one cup of milk
100% DV = 1,000mg calcium
130% DV = 1,300mg calcium


Nutrients Without a %DV: Trans Fats, Protein, and Sugars:
(Note: Trans fat, Sugars and, Protein do not list a %DV on the Nutrition Facts label.)

Trans Fat: Experts could not provide a reference value for trans fat nor any other information that FDA believes is sufficient to establish a Daily Value or %DV. Scientific reports link trans fat (and saturated fat) with raising blood LDL ("bad") cholesterol levels, both of which increase your risk of coronary heart disease, a leading cause of death in the US.

Important: Health experts recommend that you keep your intake of saturated fat, trans fat and cholesterol as low as possible as part of a nutritionally balanced diet.

Protein: A %DV is required to be listed if a claim is made for protein, such as "high in protein". Otherwise, unless the food is meant for use by infants and children under 4 years old, none is needed. Current scientific evidence indicates that protein intake is not a public health concern for adults and children over 4 years of age.

Sugars: No daily reference value has been established for sugars because no recommendations have been made for the total amount to eat in a day. Keep in mind, the sugars listed on the Nutrition Facts label include naturally occurring sugars (like those in fruit and milk) as well as those added to a food or drink. Check the ingredient list for specifics on added sugars.

If you are concerned about your intake of sugars, make sure that added sugars are not listed as one of the first few ingredients. Other names for added sugars include: corn syrup, high-fructose corn syrup, fruit juice concentrate, maltose, dextrose, sucrose, honey, and maple syrup.

To limit nutrients that have no %DV, like trans fat and sugars, compare the labels of similar products and choose the food with the lowest amount.

Carbohydrates: Are They Good? Are They Bad? Are They Necessary?

Carbohydrates (carbs) often get a bad rap, especially when it comes to weight gain. But they aren't all bad. Because of their numerous health benefits, carbs have a rightful place in your diet. In fact, your body needs them to function properly. But some carbohydrates are better for you than others. It's vitally important that you understand their importance and which types are healthier for you.

Simply put, carbohydrates are a type of macronutrient found in many foods and beverages. (NOTE: There are four macronutrients that you need in order to be healthy--proteins, carbs, fats, and water.) Most carbohydrates are naturally occurring in plant-based foods, such as grains. Common sources of naturally occurring carbs include fruits, vegetables, milk, nuts, grains, seeds, and legumes. Food manufacturers also add carbohydrates to processed foods in the form of starch or added sugar. The most basic carbohydrate is a sugar molecule, which joins together one or two units of carbon, hydrogen and oxygen. Other carbohydrates contain three or more units of the carbon-hydrogen-oxygen trio.

Now that you have some understanding of carbohydrates, it's important to understand that there are three main types of carbohydrates:

(1) SUGAR: Sugar is the simplest form of carbohydrate. Sugar occurs naturally in some foods, including fruits, vegetables, milk and milk products. Sugars include fruit sugar (fructose), table sugar (sucrose) and milk sugar (lactose).

(2) STARCH: Starch is made of sugar units bonded together. Starch occurs naturally in vegetables, grains, and cooked dry beans and peas.

(3) FIBER: Fiber is also made of sugar units bonded together. Fruits, vegetables, whole grains, and cooked dry beans and peas are among foods that are naturally rich in fiber.

You may see terms such as "low carb" or "net carbs" on some products, or promoted by some diet programs. But the Food and Drug Administration doesn't regulate these terms, so there's no standard meaning. Net carbs is typically used to mean the amount of carbohydrates in a product excluding fiber or excluding both fiber and sugar alcohols.

You may have heard of another term called the "glycemic index". As I discussed in my health tip yesterday, the glycemic index classifies carbohydrate-containing foods according to their potential to raise your blood sugar level. Many healthy foods, such as whole grains, legumes, vegetables, fruits and low-fat dairy products, are naturally low on the glycemic index. You need to strive to eat foods such as these so you don't spike your blood sugar. Eating foods that are high-glycemic will spike your blood sugar, leading to an energy crash, followed by the creation of an uncontrollable hunger. This type of eating, ultimately, works against fat loss. Morever, repeated eating of high-glycemic foods tends to build arterial plaque faster in your arteries which could lead to the development of cardiovascular disease. Additionally, repeated spiking of the blood sugar could lead to other problems down the road such as insulin resistance and Type II Diabetes.

Now that you have a better understanding of carbohydrates and the types that exist, you may be wondering how many carbohydrates you actually need. The 2010 Dietary Guidelines for Americans recommends that carbs make up 45 to 65% of your total daily calories. So, if you take in 2,000 calories a day, between 900 and 1,300 calories should come from carbohydrates. That translates to between 225 and 325 grams of carbs a day.

You can find the carbohydrate content of packaged foods by reading the Nutrition Facts label. The Nutrition Facts label shows total carbohydrates, which includes starches, fiber, sugar alcohols, and naturally occurring and added sugars. It may also list total fiber, soluble fiber and sugar separately. You may also be able to find nutrient calculators online or find information on a manufacturer's website.

Now that you have a general understanding of carbohydrates, the three types of carbs that exist, the glycemic index of carbohydrates, and the amount of carbs that you actually need, you may be wondering why they are necessary for good health.

Despite their bad rap, carbohydrates are vital to your health for a number of reasons. First of all, your body uses carbohydrates as its main fuel source. Sugars and starches are broken down into simple sugars during digestion. They're then absorbed into your bloodstream, where they're known as blood sugar (glucose). From there, the glucose enters your body's cells with the help of insulin. Some of this glucose is used by your body for energy, fueling all of your activities, whether it's going for a jog or simply breathing. Extra glucose is stored in your liver, muscles and other cells for later use or is converted to fat.

(As a side note, insulin, whose release is triggered by the presence of carbohydrates, helps amino acids [the fundamental building block of protein] enter muscle cells, which is very important in order to tone or gain muscle. In this way, carbohydrates and protein work together. Gaining muscle, incidentally, is the most efficient way to lose fat as your body requires energy to maintain muscle.)

In addition to being the primary source of energy for your body (and triggering the release of insulin which helps amino acids get into the muscle more efficiently), carbohydrates also protect you against disease. There is evidence that whole grains and dietary fiber from whole foods helps reduce your risk of cardiovascular diseases. Additionally, many large studies have found that people with higher intakes of dietary fiber and whole grains have a lower risk of colorectal cancer. New research shows that people with the highest intakes of dietary fiber have a lower risk for cancer of the small intestine. Fiber may also protect against obesity and type 2 diabetes. And as many people know, fiber is also essential for optimal digestive health.

Another health benefit to carbohydrates is that they aid in controlling weight. Evidence shows that eating plenty of vegetables, fruits 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. Contrary to what some weight-loss diets claim, very few studies show that a diet rich in healthy carbohydrates leads to weight gain or obesity.

And one final benefit of carbohydrates is that the foods that comprise them typically carry along many other important nutrients.

Hopefully, you are beginning to understand that carbohydrates are an essential part of a healthy diet. But you must choose carbohydrates wisely. As I discussed earlier, all carbs are NOT created equal. Seek out carbohydrates that are low-glycemic. A number of websites provide free databases of glycemic index values. Here is one of the more established, comprehensive ones:

http://www.mendosa.com/gilists.htm

Another website - designed by the University of Sydney - provides a searchable database where you can search by food name, glycemic index, or glycemic load:

http://www.glycemicindex.com/ (Select the GI database link from the left-hand menu)

Also, remember that it's not just important to eat carbohydrates. It's important to make carbohydrates part of a balanced diet (which includes healthy proteins and healthy fats.) To make healthy carbohydrates work in a balanced diet, do the following five things:

(1) Emphasize fiber-rich fruits and vegetables. Aim for whole fresh, frozen and canned fruits and vegetables without added sugar. They're better options than are fruit juices and dried fruits, which are concentrated sources of natural sugar and therefore have more calories. Also, whole fruits and vegetables add fiber, water and bulk, and help you feel fuller on fewer calories.

(2) Choose whole grains. All types of grains are good sources of carbohydrates. They're also rich in vitamins and minerals and naturally low in fat. But whole grains are healthier choices than are refined grains. Whole grains are better sources of fiber and other important nutrients, such as selenium, potassium and magnesium. Refined grains go through a process that strips out certain parts of the grain — along with some of the nutrients and fiber.

(3) Stick to low-fat dairy products. Milk, cheese, yogurt and other dairy products are good sources of calcium and protein, plus many other vitamins and minerals. Choose the low-fat versions, though, to help limit calories and saturated fat. And beware of dairy products that have added sugar.

(4) Don't forget beans and legumes. Legumes — beans, peas and lentils — are among the most versatile and nutritious foods available. Legumes are typically low in fat, contain no cholesterol, and are high in folate, potassium, iron and magnesium. They also have beneficial fats, and soluble and insoluble fiber. Because they're a good source of protein, legumes can be a healthy substitute for meat, which has more saturated fat and cholesterol.

(5) Limit added sugars. Added sugar probably isn't harmful in small amounts. But there's no health advantage to consuming any amount of added sugar. In fact, too much added sugar, and in some cases naturally occurring sugar, can lead to such health problems as tooth decay, poor nutrition and weight gain.So choose your carbohydrates wisely. Limit foods with added sugars and refined grains, such as sugary drinks, desserts and candy, which are packed with calories but low in nutrition. Instead, go for whole grains and fruits and vegetables.

I hope this information helps you to make healthier decisions for you and your family.

Health Tips for Expectant Mothers

In honor of Mother's Day, I posted health tips on my facebook page this week that focused on expectant mothers. In summary, I discussed the importance of consuming at least 400 micrograms of folic acid per day for women who are currently pregnant, or planning to become pregnant. The easiest way to obtain this level is through a pharmaceutical-grade nutritional supplement. However, there are natural sources of folic acid: green leafy vegetables, nuts, beans, citrus fruits,and inside many fortified breakfast cereals. In my health tips, I also discussed the importance of taking an iron supplement with somewhere between 28 and 90 mg of elemental iron per day, depending on an expectant mother's needs. Iron helps both the mother and baby's blood carry oxygen. And I also discussed the importance of supplementing with essential fatty acids like DHA. DHA, or Docosahexaenoic acid (an omega-3 essential fatty acid) is an important fat in the nerve cells of fetal and infant brains. DHA is also an important structural component of the retina and is therefore essential for eye development and growth. I mentioned that some health authorities have even recommended fortifying commercially prepared infant formulas with DHA to support health and nervous system development.

In my blog this week, I want to expand on the importance of fish oil (which contains essential fatty acids) during pregnancy and then discuss a few other nutrients that are important for women who are pregnant, or planning to become pregnant.

A study in the March 2008 issue of the "American Journal of Clinical Nutrition" looked at the importance of DHA (an omega-3 essential fatty acid) for neural development. It is speculated that DHA intakes are low enough in some pregnant women to impair infant development. The study looked at DHA in pregnant women and its relationship to early visual acuity in infants. The study compared eye development scores among infants of women who supplemented with DHA versus infants of women with typical diets. In the study, more infant girls in the placebo group than in the DHA group had a visual acuity below average and maternal red blood cell fatty acids were inversely related to visual acuity in both boys and girls. These results suggest that some pregnant women in the study population were DHA-deficient.

A separate study in the July 2008 issue of the "American Journal of Clinical Nutrition" shows a significant correlation between fish oil intake during pregnancy and asthma incidence during childhood. Children whose mothers supplemented with fish oil during pregnancy were significantly less likely to be diagnosed with childhood asthma than children from non-supplementing mothers. This provides strong evidence that fish oil intake during pregnancy may be associated with lower asthma incidence during childhood.

So for multiple reasons discussed in the previous two paragraphs, fish oil appears to have an important protective benefit for pregnant women.

Additionally, it has been suggested that maternal zinc intake influences growth in utero and in the first stages of growth after birth. In another study in the "American Journal of Clinical Nutrition" that was released in July 2008, researchers assessed the effect of maternal zinc supplementation during pregnancy as well as its effects on infant growth during the first twelve months. It was determined that infants born to mothers that supplemented with zinc had significantly larger average growth measures beginning at 4 months and continuing through month 12. Prenatal zinc was associated with greater weight, calf circumference, chest circumference, and calf muscle area.

Moving on to another important nutrient, vitamin D status is often poor in women of childbearing age, and evidence suggests that the risk of bone fracture (due to osteoporosis) in adulthood could be determined partly by environmental factors during pregnancy and early childhood. A recent study investigated the effect of maternal vitamin D status during pregnancy on childhood skeletal growth. In this study, 31% of mothers had insufficient vitamin D levels, while another 18% had deficient levels during late pregnancy. Inadequate vitamin D in mothers during late pregnancy was associated with reduced whole-body and lumbar spine bone mineral content in children at age 9. Maternal vitamin D insufficiency is common during pregnancy and now looks to be associated with reduced bone-mineral accumulation in offspring during childhood. Vitamin D supplementation of pregnant women, especially during winter months, could lead to improved bone health and a long-term reduction in the risk of osteoporosis in their children.

Equally important, supplementing with calcium during pregnancy can prevent a new mother from losing her own bone density, as the fetus uses the mineral for bone growth.

And in one final study that was published in the "Canadian Medical Association Journal" in June 2009, research shows that women who supplement with multivitamins (which contain multiple key nutrients) have a lower risk of delivering a low birth weight infant compared to those who receive only standard iron and folic acid supplements. An inadequate intake of micronutrients during pregnancy increases the
possibility of nutritional deficiencies that can affect the normal growth of the baby. Low birth weight is often associated with increased infant mortality.

Hopefully, this blog article was helpful to you. My wish is for all of those who are pregnant, or planning to become pregnant, to have healthy, happy babies! Happy Mothering!



SOURCES:

American Journal of Clinical Nutrition, Vol. 87, No. 3, 548-557, March 2008
American Journal of Clinical Nutrition, Vol. 88, No. 1, 167-175, July 2008
American Journal of Clinical Nutrition, Vol. 88, No. 1, 154-160, July 2008
Lancet 2006 Jan 7;367(9504):36-43
Canadian Medical Association Journal 6/2009; 180(12).

How Do You Reduce Your Risk Of Developing Macular Degeneration?

Macular degeneration, or age-related macular degeneration (AMD), is a leading cause of vision loss in Americans 60 and older. It is a disease that destroys your sharp, central vision. You need central vision to see objects clearly and to do tasks such as reading and driving.

AMD affects the macula, the part of the eye that allows you to see fine detail. It does not hurt, but it causes cells in the macula to die. In some cases, AMD advances so slowly that people notice little change in their vision. In others, the disease progresses faster and may lead to a loss of vision in both eyes. Regular comprehensive eye exams can detect macular degeneration before the disease causes vision loss. While treatment can slow vision loss, it does not restore vision. AMD is the most common cause of vision loss in developed countries.

This week, I discussed several studies (on my facebook page) which looked at macular degeneration. In summary, the studies I discussed concluded that you may reduce your risk of developing macular degeneration by doing the following:

* Supplementating daily with the two nutrients known as lutein and zeaxanthin
* Protecting the eyes from sunlight exposure (using hats or protective sunglasses) AND consuming high levels of dietary antioxidants such as vitamin C, vitamin E, zeaxanthin, and zinc
* Eating foods (carbohydrates) which have a low glycemic index (such as oatmeal)

While I only discussed one study detailing the benefits of lutein and zeaxanthin in reducing the risk of AMD, I want to call attention to the fact that numerous studies have pointed to the importance of lutein and zeaxanthin in maintaining eye health.

A separate study published in the September 2007 issue of the journal Archives of Ophthalmology provides more evidence that zeaxanthin and lutein may protect against AMD. In this report, members of the Age-Related Eye Disease Study (AREDS) Research Group evaluated the diets of 4,519 AREDS participants aged 60 to 80 years. Retinal photographs were used to divide the subjects into five categories of macular disease severity, from individuals with little or no evidence of macular degeneration (the control group) to severe, neovascular disease. Dietary questionnaires were analyzed for lutein, zeaxanthin, beta- carotene, lycopene, and other nutrient levels. Participants whose intake of lutein and zeaxanthin were greatest had a significantly lower risk of AMD than those whose intake was least, and were less likely to have large or extensive intermediate drusen, the deposits on the retina or optic nerve that characterize the disease. No risk reductions were associated with the other nutrients examined in this study.

In yet another study conducted at the University of Georgia in 2008, lutein and zeaxanthin were found to improve eye health by reducing the harmful effects of glare on a test group of people with normal eyesight. Healthy subjects with an average age of 23.9 were assigned to receive daily supplements of lutein (10 mg) and zeaxanthin (2 mg) for six months. The subjects' eyes were then tested for the effects of glare as experienced in everyday situations, including being outdoors on bright days, lengthy sessions of looking at a computer monitor, and nighttime exposure to oncoming headlights. Following six months of supplementation, the participant's average macular pigment optical density (MPOD) increased significantly from the average value at the beginning of the study. MPOD is a measure of the eye's ability to filter short-wave light. After testing the subjects for their performance in visual tasks following glare, researchers concluded that four to six months of supplementation with lutein and zeaxanthin significantly reduced the detrimental effects of the exposure and improved visual performance.

Before I move on to a couple of other studies, I want to talk some more about the nutrients lutein and zeaxanthin. Lutein is located in the central area of the human retina (known as the macula), and it is the predominant nutrient in the periphery of the macula. Zeaxanthin is concentrated more in the center. While the roles lutein and zeaxanthin play in the physiology of the eye are not completely understood, the links between lutein and eye health are so strong that several national and regional health organizations have recommended increasing dietary lutein intake. To maintain eye health, both lutein and zeaxanthin help screen out high-energy light, protecting underlying tissues from photo-induced damage. They also act as antioxidants, helping to protect the macula from damage due to oxidative stress. Both functions, as have been shown in studies, can help reduce the risk of age-related eye disease.

So where do we get lutein and zeaxinthin? They are found together in many food sources. Dark green leafy vegetables are the primary source, but they are also present in lesser amounts in other colorful fruits and vegetables, including broccoli, orange peppers, corn, peas, persimmons, and tangerines. Unfortunately, most dietary surveys indicate that few people consume optimal amounts of lutein and zeaxanthin-rich foods. In fact, average dietary intake in the U.S. is only 2 mg/day, far below the 6 mg/day level most studies indicate as a minimum needed to reduce the risk of AMD. This is where a supplement can fill in the missing gap, and is indeed the reason supplements, like multivitamins, are necessary. They fill in the missing gap. They do not replace a healthy diet. They add to, or supplement, a healthy diet.

Numerous studies are also concluding that you may reduce your risk of developing macular degeneration by eating fish, or supplementing with omega-3 fatty acids.

As evidence to that, a study was conducted in 2008 involving lutein and DHA (Docosahexanoic acid - an omega-3 fatty acid found in the retina of the eye). It was shown that both may help prevent macular degeneration. The study was conducted at Tufts University in Boston. In the study, researchers randomly assigned 49 women (between 60 and 80 years old) to one of four groups: placebo, DHA (800 mg/d), lutein (12 mg/d), or a combination lutein + DHA supplement. The objective of this four month study was to determine the effects of lutein and DHA on the women's serum concentrations and macular pigment optical density (MPOD). In all supplement groups, blood nutrient levels were higher at two and four months than at the beginning of the study. DHA supplementation resulted in central increases of macular pigment density, while lutein was associated with eccentric, or away from the center, increases. It was then concluded that supplementing lutein and DHA may help reduce the risk of age-related macular degeneration by increasing MPOD, helping protect the macula from oxidative damage, and increasing lutein transport into the macula.

In another study conducted in 2008, it was determined that eating one portion per week of fish rich in omega-3 fatty acids may reduce the risk of age-related macular degeneration (AMD) by over 50%. Fish intake is the major source of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA). So that you are clear on AMD, there are actually two types: wet AMD and dry AMD. Of these two types, wet AMD is the primary cause of vision loss. In this particular study, which was published in the American Journal of Clinical Nutrition, researchers recruited 105 people (age 65 and over) with wet AMD and 2170 healthy people to act as controls, then compared their dietary habits using questionnaires. The scientists then investigated the association of oily fish and dietary DHA and EPA with wet AMD. Compared to people who consumed less than one portion of fish per week, participants who consumed at least one serving of oily fish per week had a 50% reduction in risk of developing wet AMD. In addition, people who got at least 300 mg per day of DHA and EPA were 68 and 71% less likely to have wet AMD than those with lower consumptions. The results of this study support previous research indicating a protective benefit of omega-3s against the onset of AMD. The benefit may be due in part to their important role in the layer of nerve cells in the retina.

And in two other studies published in the May 2007 Archives of Ophthalmology, it was shown that vitamin D and the omega-3 fatty acids from fish may help lower the risk of developing AMD. In the first study, researchers evaluated habitual nutrient intake through food frequency questionnaires of over 4,500 people between ages 60 and 80 who participated in a study by the National Institute of Health's National Eye Institute. Researchers found that higher dietary intakes of omega-3 long-chain polyunsaturated fatty acids, mainly from fatty fish, reduced the risk of age-related macular degeneration. The researchers speculate that these fatty acids may help promote cell health and survival as well as improve blood vessel function. In the second study, researchers evaluated serum vitamin D and early and advanced macular degeneration in over 7,752 individuals from the National Health and Nutrition Examination Survey III (NHANES III). Researchers noted that vitamin D intake was associated with a reduced risk of developing poor visual health that can lead to blindness. Participants were split into five groups based on the level of vitamin D in their blood. Those with the highest level had a 40% reduced risk of developing poor visual health compared with those with the lowest amount of vitamin D in their blood. These results support the idea that lower serum vitamin D levels may lead to progression of chronic diseases, specifically those associated with inflammation. This may be important to the health of older Americans who have a higher risk of insufficient vitamin D intake, the researchers said. While these results are promising, researchers caution that at this time there is insufficient epidemiologic evidence of the relationship between vitamin D and age-related macular degeneration to make recommendations regarding optimum vitamin D levels and fish intake to protect against the eye disease or its progression. These results warrant additional investigation to further confirm the role of omega-3 long-chain polyunsaturated fatty acids and vitamin D in AMD.

I know I presented an extensive list of studies, but I did so to make the point that there is strong evidence that you may reduce your risk of developing macular degeneration. These studies indicate that you can reduce your risk by:

(1) Supplementating daily with the two nutrients known as lutein and zeaxanthin;
(2) Protecting the eyes from sunlight exposure (using hats or protective sunglasses) AND consuming high levels of dietary antioxidants such as vitamin C, vitamin E, zeaxanthin, and zinc
(3) Eating foods (carbohydrates) which have a low glycemic index (such as oatmeal); and
(4) Eating fish, or supplementating with omega-3 fatty acids



SOURCES:

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