Nutrition in the News is written by Beth Grainger, RDN, PhD, is a Grandview Heights Schools parent and a senior research nutritionist in the Laboratory of Bionutrition and Cancer at The Ohio State University Comprehensive Cancer Center. Dr. Grainger’s area of research interest includes human clinical trials focusing on nutrition assessment, plant phytochemicals, and dietary patterns in cancer prevention and survivorship.
Nutrition in the News – The Sunshine Vitamin
By Beth Grainger, RDN, PhD
I recently came across another article describing a role of vitamin D in treatment of COVID-19. It’s still too early to speculate on this relationship (if there is one); but as the days get longer, it seems appropriate to spotlight vitamin D.
Vitamin D is unique among nutrients for several reasons. First, we can synthesize vitamin D when our skin is exposed to the sun. Because sunlight significantly contributes to vitamin D levels in the blood, early research studied populations of people who had no sun exposure for extended periods of time, like submariners and people living in Antarctica. These studies, as well as more contemporary research, helped establish that kids and adults need around 600 International Units (IU) of vitamin D each day to maintain health and promote bone density. Of course, this recommendation may change as science evolves and we learn more about the role of vitamin D in chronic diseases like heart disease and cancer.
A second unique quality of vitamin D is that unlike most other vitamins, vitamin D functions like a hormone and can bind to receptors on DNA and alter gene expression. Vitamin D helps the body retain calcium and phosphorous and is critical for bone health, especially in kids and adolescents. Without adequate vitamin D, only about 10-15% of calcium from the diet is absorbed.
Third, a vitamin D deficiency (measured by a blood test) is very common in kids and adults. Unlike other nutrients, vitamin D is only found in a handful of foods (fortified milk, fatty fish, mushrooms) and limited sun exposure further increases the risk of deficiency. Around 25% of kids and 40% of adults have suboptimal blood vitamin D concentrations! Furthermore, people with dark skin make less vitamin D from the sun and therefore are even more likely to be deficient. This is in stark contrast to most other nutrients where deficiencies are relatively uncommon due to availability in a wide variety of foods. Fortified milk is a major source of vitamin D in the American diet and provides around 120 IU per cup. There are other fortified foods (such as orange juice, non-dairy milks), but check the label if you want to be sure you’re choosing a fortified food.
Supplements can be worthwhile if you have been diagnosed with insufficient or deficient vitamin D levels. But remember, nutrition is all about balance and too much of any one nutrient can upset that balance. Here are a few links with more information.
Nutrition in the News – Revisiting 5-A-Day
By Beth Grainger, RDN, PhD
Science news over the past year has been dominated (and rightfully so) by the evolving research related to SARS-CoV-2 and COVID-19. As many home cooks were trying to grow sourdough starters in our kitchens, nutrition research in labs all over the world continued to progress.
This week, a study was published in an American Heart Association journal that was widely circulated among news outlets. The conclusion was nothing out of the ordinary: fruits and vegetables are good for you and eating them can help reduce disease risk. But the details answered some questions that many nutrition scientists have pondered.
First, if five servings of fruit and vegetables is good for you, are more servings better? The answer here was not really. The benefits of fruits and vegetable plateaued with intake over five servings per day. Second, is it OK to eat a lot of fruit and not many vegetables (or vice-versa)? In this study, the most protective combination was two fruit servings and three vegetable servings per day. Finally, two of the most common fruits and vegetables in the American diet are fruit juice and potatoes. Do these foods count toward the 5-a-day goal? Although starchy vegetables and 100% juice have some important nutrients, they did not contribute to the lower mortality and lower disease burden in this large study.
Nutrition in the News – Diet, Health, and the Microbiome
By Beth Grainger, RDN, PhD
This week, a student in our laboratory at Ohio State presented his doctoral thesis work, which focused on dietary patterns and gut microbes. I left the lecture feeling amazed by the student’s work and inspired by the progress and promise of nutritional science.
Nutrition science began in earnest around 1910 with the discovery of several of the B vitamins. Over the next forty years, one by one, other vitamins and minerals were discovered, isolated in laboratories, and used to eradicate common nutrient deficiency diseases, like scurvy, pellagra and goiter. By the 1950’s all of the nutrients had been discovered, Recommended Dietary Allowances (RDA’s) were established and public health efforts were underway. Food fortification programs were instituted and public health guidelines were starting to develop as more connections were made between diet and disease.
Nutrition research has continued to evolve and address much more complex issues, but many would argue that the current era of nutrition research is perhaps the most exciting. This is due in part to the fascinating world of the microbiome. The human body contains 5-10 times more microorganisms than cells. These populations of “bugs” can be found everywhere: on our skin, the surface of our eyes, and of course throughout our intestinal tract. The microbes in our gut can stimulate our immune system, protect us from pathogens, and metabolize the foods we eat. Studies in kids suggest specific patterns of gut microbes are associated with everything from asthma to behavior and mood, although cause-and-effect has not been determined. We are just beginning to learn about diet, microbiome and health relationships; some families of microbes confer health benefits and other are associated with disease. The type and amount of microbes in our gastrointestinal system is directly affected by the foods we eat. A recent study employed a well-known index called the Healthy Eating Index, which scores the quality of an individuals diet. In this study, subjects with a low score reported a low dietary intake of fruits, vegetables and whole grain foods and a high intake of refined sugar and had a more of the harmful bacteria, and less of the bacteria thought to be beneficial. There are a few consistent findings with all of this research: eat foods containing fiber and eat foods with live cultures. In your gut, fiber is the major food source for all those beneficial microbes. Without adequate fiber, the bacteria will start to eat away at the protective lining of the gastrointestinal tract, which can lead to a host of digestive and other illnesses. There are a lot of great resources to learn more about the microbiome; here is a nice review.
Nutrition in the News – Nutrition Facts Upgrade
By Beth Grainger, RDN, PhD
January 1, 2020, is a day many in the field of nutrition have been waiting for. As of this day, the “new” Nutrition Facts panel found on the labels of all packaged foods is required for almost all food manufacturers. Some companies started using label months ago and small food companies have until 2021 to comply. The revised label was actually approved by the FDA in 2016, but various issues have delayed its implementation.
The new Nutrition Facts panelhas a number of improvements; from updated serving sizes to the inclusion of vitamins and minerals that are commonly low in the American diet. Most significantly, however, is the inclusion of “added sugars” under the total carbohydrate heading. As a population, it is no secret that we eat too much added sugar. The recommendations for adults are no more than 10% of total calories (which equates to 25-50 grams of sugar per day). The recommendations for kidsis 25 grams or less per day (this is equal to 6 teaspoons). The average added sugar intake among people over the age of 2 is 84 grams per day.
Extra sugar contributes calories to our diet, but no vitamins, minerals or phytochemicals and too much sugar contributes to a host of ill effects on health. The vast majority of added sugars come from the following food categories: soda/soft drinks, candy, desserts (cookies, pie, cake etc) and fruit drinks (including juice). Previously, it has been difficult to look at a label and differentiate between sugar added to a food during processing and sugars naturally present in foods. The new label will allow consumers to see how much sugar is added to a food product and determine if it is a healthy choice.
Here are a few tips to reduce sugar in your kids diet. The long-awaited new Nutrition Facts panel should make any New Year’s resolution to reduce added sugar a bit easier.
Nutrition in the News – Diet and Vision Health
By Beth Grainger, RDN, PhD
For a few years now, I have written a monthly article associated with Foodie Friday. As Foodie Friday has grown and evolved, so has this column, which will now feature a monthly article focusing on contemporary nutrition issues that affect parents and children.
This month I would like to address a nutrition story published in September that probably shocked kids and parents alike. It was a report of a teenager in England who became blindafter years of consuming a severely restricted diet. Could this be true? While the details of this particular case are not available, the role of nutritionin healthy vision has been known for a century. In fact, a vitamin A deficiency is the leading cause of blindness among kidsin the world with over 300,000 children across the globe going blind every year because of inadequate nutrition.
Beta-carotene (found in orange and red fruits and vegetables like carrots and sweet potatoes) is converted to vitamin A and provides much of the nutrient in American diets. Non-nutrient components of plant foods (also called phytochemicals) are additionally important in healthy vision. Lutein and zeaxanthin from spinach, Brussels sprouts and other green or yellow vegetables accumulate in the macula and can help prevent macular degeneration. Finding ways to get children to eat orange, green and yellow vegetables can be challenging, but it is really important. Here are some strategies to help you help your children establish good nutritional habits.