Newsletter Article

Sickle Cell Anemia

October 2016

Sickle cell anemia is an inherited disease that affects the red blood cells. Healthy blood cells are rounded, flexible, and move easily through the blood vessels.[1] When blood cells are affected by sickle cell anemia, they are shaped like a crescent moon, rigid, and sticky. They can become stuck in blood vessels, which can slow or even block the flow of blood to parts of the body. Because blood vessels can become obstructed or blocked, this puts those with sickle cell anemia at greater risk for certain conditions, such as stroke, acute chest syndrome, organ damage, blindness, and gallstones.

Sickle cell anemia is the most common inherited disease in the world.[2] A person has sickle cell anemia if they received two copies of the mutated gene from their parents. Sickle cell trait is when a person only received one mutated gene. Their blood cells are normally shaped and may have no complications.

A study used a six- minute walk test to determine hemoglobin oxygen saturation levels in children with sickle cell anemia and in children with sickle cell trait.[3] Before the test, oxygen saturation levels were taken at rest, and researchers found that none of the children with sickle cell trait showed desaturation, while 50% of the children with sickle cell anemia had mild to moderate desaturation. After the six-minute walk test, saturation levels were again measured and showed that 18% of the children with sickle cell trait and 34% of the children with sickle cell anemia had ≥ 3% decrease in saturation. This shows that those with sickle cell anemia may have a greater risk for pulmonary and cardiovascular complications.

Due to metabolic changes that occur during exercise, sickling of the blood cells may be initiated with higher levels of exercise.[4] It is recommended that people with a sickle cell disorder start exercise slowly and progressively. There is a higher risk for developing rhabdomyolysis during intense activity for those with sickle cell trait.[5] Rhabdomyolysis can cause serious kidney damage, kidney failure, and if not treated, potentially death. Because intense activity is not recommended, lower activity levels are needed to maintain health for individuals with sickle cell disorders.


Onions are members of the allium family.[6] Onion comes from the latin word unio meaning “single,” which refers to the single bulb that onions produce. The two main types of large onions are spring/summer onions and storage onions. The spring/summer varieties are grown in warm climates and have a mild or sweet taste such as the Sweet Onion or the Vidalia. Storage onions are grown in cooler climates and are typically more pungent. There are also smaller varieties including the green onion, pearl onion, and scallions.

Onions are rich in sulfur-containing compounds that give them their pungent odor. There is evidence to show that these sulfur compounds may help prevent unwanted blood clotting, lower cholesterol, and improve cell membrane function in red blood cells. Onions also contain a health-promoting flavanoid called quercetin, which has been shown to reduce the oxidative stress on cells and may reduce the risk of developing certain types of cancer. Quercetin has also shown antibacterial effects on several strains of streptococcus and other bacteria. Some studies have suggested that eating onion just 1-2 times per week may lower cancer risk. More consumption was linked to lower risks with additional types of cancer.

When selecting onions, choose ones that have no openings at the neck, have a crisp, dry outer skins, have not sprouted, and have no signs of mold. For storage, onions should not be kept refrigerated, unless they are green onions. They should be kept in a well ventilated space and away from heat and bright light. They should also be kept away from potatoes, as they will absorb their ethylene gas and spoil more quickly.

Onions are extremely flavorful and versatile, and are a healthy and easy addition to a variety of meals.

5-Minute French Onion Soup

2 tablespoons butter
2 cups sweet onions, sliced thin
4 cups beef broth
4 baguette slices
Several slices of Gruyere cheese

Preheat oven to 450 degrees. Bake baguette slices in the oven while you prepare the soup. In a large pot, melt the butter and cook the onions until very soft, about 3-5 minutes. Pour the beef broth in the pot. Season with salt & pepper according to taste. There, that’s it! The soup is ready! (If you desire to let the soup simmer, that’s okay, too! It will become more flavorful as you let it cook).

Spoon the soup into medium ramekins, then transfer the ramekins to a cookie sheet. Turn the oven to broil and raise the oven rack to it’s highest position. Place a toasted baguette in the center of the soup, cover completely with cheese slices, then broil until the cheese is melted and bubbling, about 1 minute or so. Serve immediately.

Recipe from

Tissue Flossing

Every professional athlete and weekend warrior is always looking for a way to be better at his or her sport. One way to improve is by simply training more. In order to do this, a quick recovery between competitions and training sessions is necessary. Nagging injuries and sore muscles can keep athletes from training. One method of speeding recovery started in CrossFit circles and is something called tissue flossing, made famous by Voodoo Floss. The idea is that you use a compression band to tightly wrap a joint or muscle area, and then go through a series of movements. This is supposed to help relieve muscle and joint pain, as well as increase range of motion. There are several purported reasons for its effectiveness, but there is minimal research on the technique. The main claims are that it works by using myofascial release, blood flow occlusion, and joint centration.

The tissue flossing method was used on the shoulders of male athletes to compare the range of motion and strength to a controlled warmup.[7] Using the tissue flossing, there was a greater range of motion for internal and external shoulder rotation, but it was not significant. There was not a difference in strength measures on bench press between the protocols. These were not athletes with shoulder injuries or issues, which could have a different outcome since this method is typically used when there is pain at a muscle or joint area that needs to be relieved.

There is a lot of anecdotal evidence that this type of recovery is effective, by there is almost no published research to back up the claims. As with any self-help product, do your own research and be careful if you decide to try it out.

Health Matters is written by Lindsey Guthrie, MS, RD, LD/N and Tyler Guthrie, MS, CSCS.


  1. The Mayo Clinic. Sickle Cell Anemia.
  2. Scientific American. Exercising Caution: Intensive Athletic Activity Could Be Fatal to Those with Sickle-Cell Trait.
  3. Waltz X, Romana M, Lalanne-Mistrih ML, et al. Hematologic and hemorheological determinants of resting and exercise-induced hemoglobin oxygen desaturation in children with sickle cell disease. Haematologica. 2013; 98(7): 1039.
  4. Connes P, Machado R, Hue O, Reid H. Exercise limitation, exercise testing and exercise recommendations in sickle cell anemia. Clinical Hemorheology and Microcirculation. 2011 49(1-4): 151.
  5. Nelson DA, Deuster PA, Carter R, et al. “Sickle Cell Trait, Rhabdomyolysis, and Mortality among US Army Soldiers.” New England Journal of Medicine 2016; 375(5): 435.
  6. The George Mateljan Foundation. Onions.
  7. Plocker D, Wahlquist B, Dittrich B. Effects of Tissue Flossing on Upper Extremity Range of Motion and Power. International Journal of Exercise Science: Conference Proceedings. 2015; 12(1).

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