The Facts

Nutritional Factors

Published on Monday, 08 October 2012 15:23

At Foodfacts.com, we get many questions about how and why a particular nutrient affects a product's score.  It's our nutrition department to the rescue with an explanation for some of the most common nutrients and values that factor into our unique, patent-pending Health Score.

ADDED SUGARS

The USDA defines added sugars as sugars, syrups and other caloric sweeteners that are added to foods during processing, preparation, or consumed separately. Added sugars do not include naturally occurring sugars such as those in fruit or milk.

Added sugars provide empty calories, which are calories without any nutrients.  This may contribute to weight gain as empty calories do not provide a feeling of satiety the way that fibers, fats or proteins do. Beyond simple weight gain, some research shows a possible association between increased sugar intake and heart disease and pancreatic cancer. For optimum health, added sugars should be limited to six to nine teaspoons a day. The World Health Organization recommends a limit of 10% of calories coming from added sugars, and the American Heart Association recommends a limit of 5% of calories coming from added sugars.  Much of the added sugar we consume comes from sweetened beverages, candies, desserts and sugary cereals. Home use of sugars is minimal compared to processed foods; for example, adding two teaspoons of honey to tea is minimal compared to the 10 teaspoons found in a 12 fl oz can of soda.

Added sugars include: brown sugar, corn sweetener, corn syrup, dextrose, fructose, fruit juice concentrates, glucose, high-fructose corn syrup, honey, invert sugar, lactose, maltose, malt syrup, molasses, raw sugar, turbinado sugar, trehalose, sucrose, and more.

CHOLESTEROL

Cholesterol is a natural sterol present in all animal tissues. Free cholesterol is a component of cell membranes and serves as a precursor for steroid hormones (estrogen, testosterone, aldosterone) and for bile acids. Humans are able to synthesize sufficient cholesterol to meet biologic requirements; there is no evidence for a dietary requirement for cholesterol.

Moderate evidence from epidemiologic studies relates dietary cholesterol intake to clinical cardiovascular disease (CVD) end-points. Many randomized clinical trials on dietary cholesterol use eggs as the dietary source. Independent of other dietary factors, evidence suggests that consumption of one egg per day is not associated with risk of coronary heart disease or stroke in healthy adults, although consumption of more than seven eggs per week has been associated with increased risk. An important distinction is that among individuals with type 2 diabetes, increased dietary cholesterol intake is associated with CVD risk.

The types of fat in the diet determine to a large extent the amount of total, HDL, and LDL cholesterol in the bloodstream. The types and amount of carbohydrate in the diet also play a role. Cholesterol in food matters too, but not nearly as much.

DIETARY FIBER

Dietary fiber is a non-digestible form of carbohydrates and lignin. It is naturally occurring in plant foods and has beneficial health properties. There are different ways to categorize fiber, such as functional and dietary fiber, or the more popular terms “soluble” and “insoluble.”

Soluble fiber absorbs water.  It can help lower cholesterol, increase insulin sensitivity and delay stomach emptying, which leads to a feeling a fullness.   Insoluble fiber does not absorb water.  It helps prevent constipation, passes through intestines intact, and shortens transit time in gut.

The health benefits of a diet high in fiber include reduced risk of heart disease, type 2 diabetes, diverticular disease and constipation. Fiber may also help with weight control, since it provides a feeling of satiety. It is worth noting that as fiber intake increases, so too should water intake as fiber absorbs water. Foods with naturally occurring fiber, such as legumes, nuts, seeds, fruits, vegetables and whole grains, can also increase the nutrient density of one’s diet. It is unclear if added fiber provides the same health benefits as naturally occurring sources.  The recommendation for fiber intake is 14 grams per 1000 calories, or 25 grams per day for women and 38 grams per day for men.  The average American consumption of fiber is 15 grams per day.

Excellent sources of soluble fiber include oatmeal, oat bran, legumes, apples, chia seeds, flaxseeds, blueberries and carrots.

Excellent sources of insoluble fiber include whole grains, wheat bran, celery, broccoli, dark leafy greens, onions, tomatoes

SATURATED FATS

According to the USDA and American Heart Association, strong evidence suggests a link between increased saturated fat intake and heart disease, which is why the recommended limit for Saturated Fat is less than seven to ten percent of one’s calorie intake.   According to the 2010 Dietary Guidelines for Americans, “in addition to being a major contributor of solid fats, moderate evidence suggests an association with processed meats (e.g., franks, sausage and bacon) and increased risk of colorectal cancer and cardiovascular disease.” (p. 27)

However, foods contain a combination of different types of fatty acids and not all saturated fats are created equal. Lauric fatty acids and stearic fatty acids (found in unrefined coconut oil and cocoa, respectively) have been shown to have cardiovascular benefits!

SODIUM

Sodium is an essential nutrient that is required in our bodies in small amounts (180 – 500 mg). However, Americans ages two and older have an average daily intake of 3,436 mg  –  1,136 mg over the tolerable upper limit set by the Institute of Medicine. According to the 2010 Dietary Guidelines for Americans, there is strong evidence that correlates high sodium intake, low potassium intake and low magnesium intake to high blood pressure, which could lead to cardiovascular disease, kidney disease and congestive heart failure.

Some people may be more sensitive to the effects of a high sodium intake than others. However, the effects of increased sodium intake extend beyond high blood pressure. Increased sodium intake has also been shown to correlate with stomach cancer and osteoporosis. Food sources that are typically high in sodium are processed foods, which also tend to not provide other nutrients. It is worth noting that even if a processed food claims to be “low sodium,” it can still contain little nutritional value.

Excellent sources of low sodium, high potassium/magnesium/nutrient foods include nuts/seeds, legumes, fruits, vegetables and whole grains.

VITAMINS: NATURALLY OCCURRING vs. ADDED VITAMINS

Many foods have vitamins and minerals added to them via enrichment (replacing lost nutrients) or fortification (adding nutrients to a food). Enrichment and fortification have proven beneficial to our health.  For example: rickets, goiters and neural tube defects have decreased since foods were fortified/enriched with Vitamin D, iodine and folic acid, respectively.  However, synthetic vitamins and minerals aren’t as readily absorbed or retained in our bodies compared to naturally occurring vitamins and minerals. Further, not all nutrients that are lost during processing are replaced - refined grain foods lose dozens of nutrients in the refining process, but are only enriched with 5 nutrients.

Comparatively, naturally occurring nutrients found in whole foods have more to offer than fortified/enriched foods.  Foods with naturally occurring vitamins and minerals have the added benefit of phytonutrients that work synergistically with the vitamins in that food to contribute to our health.  For example, the flavanoids in almond skin work with the naturally occurring vitamin E to lower LDL cholesterol.

It is important to take a look at what a whole food offers, rather than focus on individual nutrients. A sugary snack that offers 20% of daily calcium needs may also come with added sugars, artificial dyes and flavors whereas a cup of milk may have added vitamin A and D, but is also a good source of protein, B vitamins, calcium and phosphorus. 


INFORMATIONAL RESOURCES:

Saturated Fat

http://ajcn.nutrition.org/content/63/6/897.abstract

http://www.nature.com/ejcn/journal/v62/n5/abs/1602756a.html

http://www.nel.gov/conclusion.cfm?conclusion_statement_id=250194

http://www.heart.org/HEARTORG/Conditions/Cholesterol/PreventionTreatmentofHighCholesterol/Know-Your-Fats_UCM_305628_Article.jsp

http://www.cnpp.usda.gov/publications/dietaryguidelines/2010/policydoc/policydoc.pdf

http://coconutoil.com/peer_reviewed/

 

Sodium

http://www.cdc.gov/Features/dsSodium/

http://www.multibene.com/pdf/Journal_of_Human_Hypertension_Final.pdf

http://www.nutritionevidencelibrary.com/topic.cfm?cat=2863

http://www.hsph.harvard.edu/nutritionsource/salt/lower-sodium-and-salt/#hazards-of-too-much-sodium

 

Added sugars:

http://articles.latimes.com/2010/apr/20/science/la-sci-sugar-20100421

http://www.medscape.org/viewarticle/547986

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC156706/

http://www.heart.org/HEARTORG/GettingHealthy/NutritionCenter/HealthyDietGoals/Sugars-and-Carbohydrates_UCM_303296_Article.jsp)

 

Cholesterol:

http://www.nel.gov/conclusion.cfm?conclusion_statement_id=250193

http://www.hsph.harvard.edu/nutritionsource/what-should-you-eat/fats-full-story/index.html#cholesterol

 

Differences between naturally occurring vs. added vitamins

http://www.ncbi.nlm.nih.gov/pubmed/15930439?ordinalpos=6&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DefaultReportPanel.Pubmed_RVDocSum

http://onlinelibrary.wiley.com/doi/10.1111/j.1750-3841.2007.00274.x/full

http://wholegrainscouncil.org/for-members/web-content-for-members

http://www.healthresearch.com/vitamins.htm

http://www.who.int/nutrition/publications/micronutrients/GFF_Part_1_en.pdf

 

Dietary fiber:

Harvard School of Public Health: Fiber: Start Roughing It

http://lpi.oregonstate.edu/infocenter/phytochemicals/fiber/

USDA Dietary Guidelines for Americans 2010