Samples of pasteurized milk on grocery store shelves have tested positive for remnants of the bird flu virus that has already infected herds of dairy cows, the U.S. Food and Drug Administration (FDA) said Tuesday.

The FDA stressed that the material is inactivated and that the findings “do not represent [an] actual virus that may be a risk to consumers.” Officials added that they’re continuing to study the issue.

Bird flu virus, known as Highly Pathogenic Avian Influenza (HPAI) or H5N1, is a disease that is highly contagious and often deadly in poultry. 

Infection with the virus causes decreased lactation, low appetite and other symptoms in affected cattle, the FDA says.

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The FDA and U.S. Department of Agriculture (USDA) said that commercial milk supply is safe because of the pasteurization process.

The pasteurization process involves killing harmful bacteria and viruses by heating milk to a specific temperature for a set period of time to make milk safer. Federal regulations require milk that enters interstate commerce to be pasteurized.

“The pasteurization process has served public health well for more than 100 years,” the FDA said. “Even if [the] virus is detected in raw milk, pasteurization is generally expected to eliminate pathogens to a level that does not pose a risk to consumer health.”

“To date, we have seen nothing that would change our assessment that the commercial milk supply is safe.”

Pasteurization is different from complete sterilization, which extends shelf life but is not required to ensure milk safety, the agency said. 

Officials with the FDA and the USDA had previously said milk from affected cattle did not enter the commercial supply. Milk from sick animals is supposed to be diverted and destroyed. 

FDA officials did not indicate how many samples they tested or where they were obtained. The agency has been evaluating milk during processing and from grocery stores, officials said. Results of additional tests are expected in “the next few days to weeks.”

The PCR lab test the FDA used would have detected viral genetic material even after a live virus was killed by pasteurization or heat treatment, Lee-Ann Jaykus, an emeritus food microbiologist and virologist at North Carolina State University told the Associated Press. 

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Cows being milked while riding a slowly-moving carousel.  (Edwin Remsberg/VW Pics/Universal Images Group via Getty Images)

“There is no evidence to date that this is [an] infectious virus and the FDA is following up on that,” Jaykus said.

Scientists confirmed the H5N1 virus in dairy cows in March after weeks of reports that cows in Texas were suffering from a mysterious malady. 

The FDA says HPAI has now been confirmed in domestic livestock in 33 herds across eight states: Idaho, New Mexico, Texas, South Dakota, Kansas, Michigan, Ohio, and North Carolina.

While the virus is lethal to commercial poultry, most infected cattle seem to recover within two weeks, experts say.

The National Milk Producers Federation (NMPF) echoed the FDA’s assertions that pasteurization is effective against HPAI and that commercial milk supply is safe.

“Viral fragments detected after pasteurization are nothing more than evidence that the virus is dead; they have zero impact on human health,” the NMPF said in a statement. 

“Further, the federal PMO prohibits milk from sick cows from entering the food supply chain. Milk and milk products produced and processed in the United States are among the safest in the world.”

Bird flu virus has been found in samples of pasteurized milk on grocery store shelves but there is no risk to customers, the U.S. Food and Drug Administration (FDA) said Tuesday. (iStock)

The news comes after a goat in Minnesota tested positive HPAI in February, which marked the first U.S. case of bird flu in domestic cattle, sheep, goats or their relatives.

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The positive juvenile goat was residing on a Stevens County farm that already had bird flu infected poultry, according to the Minnesota Board of Animal Health. 

To date, two people in the U.S. have been infected with bird flu. A Texas dairy worker who was in close contact with an infected cow earlier this year developed “eye redness” and has recovered, according to the Centers for Disease Control and Prevention (CDC).

In 2022, a prison inmate in a work program caught it while killing infected birds at a Colorado poultry farm. His only symptom was fatigue and he also recovered.

The Associated Press contributed to this report. 

Dental hygiene is important — as is taking pride in your “pearly whites.”

But keeping your teeth bright and white can be a challenge, with various factors causing discoloration.

Dr. Ronald Santana, head of science and development at Oral Biolife in Pennsylvania, noted that tooth discoloration refers to the “staining or darkening of teeth” from internal or external factors.

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“Extrinsic discoloration is caused by color changes of the tooth enamel by external factors such as smoking, foods or beverages, including coffee, tea and red wine,” he said in a statement to Fox News Digital.

“Intrinsic discoloration affects the tooth dentin and is caused by some medications taken during childhood (tetracyclines), dental trauma and certain diseases (liver disease).”

Dr. Erin Fraundorf, owner of BOCA Orthodontic and Whitening Studio in Ladue, Missouri, agreed that numerous factors can cause the discoloring of teeth.

While there is “no way to know the cause without being evaluated and diagnosed by a professional,” the expert said that diet, smoking, medications, trauma, genetics, thin enamel and the wearing down of teeth via grinding and chewing can all lead to discoloration.

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“A good general rule of thumb is that if it can stain a white T-shirt, it can stain your teeth,” she told Fox News Digital.

Santana and Fraundorf offered seven tips on how to get your teeth whiter and brighter.

1. Develop an oral care routine

Fraundorf recommended brushing at least twice a day with an electric toothbrush and using toothpaste with fluoride or nano-hydroxyapatite (nHA).

“Avoid using charcoal or other abrasive toothpastes, as they damage enamel over time, making teeth darker,” she said.

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“Transform mundane oral care into a self-care ritual to make it an experience,” she added.

While some people might feel inclined to try at-home teeth-whitening remedies, Santana stressed that “care should be exercised in selecting a safe and effective at-home approach for tooth whitening.”

Experts say it’s best to avoid using charcoal or other “abrasive” toothpastes. (iStock)

“Avoid trying at-home approaches before seeing a dentist, because some substances may damage the tooth enamel,” he warned.

“Adequate” toothbrushing is an “effective” way to reduce the discoloration of your teeth, according to Santana.

PRACTICE GOOD ORAL HYGIENE TO PROTECT YOURSELF AGAINST PERIODONTITIS

“Tooth brushing with a correct brushing technique, employing a whitening dentifrice and using an electric toothbrush are effective resources to reduce tooth discoloration.”

Fraundorf added that flossing with toothpaste, using a water flosser to remove plaque and using a tongue scraper daily to decrease bacteria can also promote whiter teeth.

2. Drink more water

Water is “the best thing you can drink to keep your teeth healthy and white,” according to Fraundorf.

“Next time you have that cup of coffee or glass of red wine, take a swig of water in between sips and briefly swish around,” she advised. 

Water is “the best thing you can drink to keep your teeth healthy and white,” a dentist suggested. (iStock)

“Water will not only prevent the staining particles from clinging onto your teeth, it will also help neutralize the acidity of the beverage.”

Fraundorf also recommended choosing flat water rather than sparkling.

“Drink and swish with it frequently to neutralize your oral environment and fight stains,” she suggested.

3. Chew sugar-free gum

Studies suggest that cavities are “significantly lower” in patients who chew sugar-free gum for 20 minutes after a meal, Fraundorf noted.

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“Chewing sugar-free gum increases salivary flow by stimulating mechanical and taste receptors in the mouth,” she told Fox News Digital. 

“Saliva helps wash away food particles as well as dilute and neutralize acids produced by plaque bacteria on teeth, leading to a reduction in cavities and stains.”

4. Drink through a straw

Using a straw, especially when drinking dark, acidic or sugary beverages, can help decrease the contact these substances make with your teeth.

Drinking through a straw decreases the liquid’s contact with your teeth, experts advised. (iStock)

“For extra credit, try drinking beverages more quickly to reduce the amount of time your oral environment is exposed to a lower pH, therefore decreasing the amount of enamel damage,” Fraundorf said.

5. Fight stains with fruits and veggies

Certain foods and drinks — such as red wine, soda, soy sauce, curry, balsamic vinegar and coffee — may stain your teeth and should be avoided, Santana said.

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“Moreover, although the scientific evidence is limited, consumption of a balanced, healthy diet — containing strawberries, grapes, apples, watermelon, papaya, pineapple, cheese, celery, carrots, broccoli and almonds — may limit tooth staining,” he noted.

Fraundorf agreed that “superfoods may be one of the best (and tastiest) ways to whiten your teeth naturally.”

Superfoods like strawberries can help whiten teeth, according to experts. (iStock)

“Strawberries, apples and watermelon all contain a lot of malic acid, which helps whiten your smile by removing surface stains and increasing saliva,” she said.

Other superfoods that can help whiten teeth include celery and leafy greens, since their “fibrous textures act like a natural toothbrush, exfoliating plaque off your teeth,” Fraundorf added.

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“Dark, leafy greens also contain calcium, counteracting the effects of acids, and an abundance of folic acid, which is essential to gum tissue cell growth.”

6. Visit the dentist

“Maintaining excellent oral health is the most important thing you can do to achieve a bright smile,” Fraundorf told Fox News Digital.

“Set a calendar reminder to get regular check-ups and cleanings with your general dentist.”

Santana added, “Your dentist can prescribe safe and customized resources for tooth whitening tailored to your specific needs.”

Patients should visit the dentist for a general check-up every six months, experts recommended. (iStock)

7. Consider professional teeth whitening

Although being diligent about oral care can help keep teeth bright, Fraundorf suggested that professional teeth whitening could be necessary to “take your smile to the next level.” 

“Maintaining excellent oral health is the most important thing you can do to achieve a bright smile.”

“Whitening treatments are not one-size-fits-all, so it is important to seek customized care,” she said. 

“The most ideal whitening treatment is one specific to you, crafted based on your unique smile goals, teeth composition, diet, sensitivity level and lifestyle.”

She added, “A multitude of factors go into a proper diagnosis and customized treatment plan for teeth whitening to ensure the best, most comfortable, beautiful results.”

Artificial tooth structures, like crowns, veneers and composites, won’t whiten, according to the expert — which means whitening these teeth will require extra restorative work.

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CrossFit offers a unique fitness experience, blending a combination of high-intensity workouts with a supportive community.

It’s important for beginners to equip themselves with the knowledge necessary to ensure a safe and successful start before diving into the program.

Read on to learn more about the program and how newcomers can make the most of their CrossFit journey.

What is CrossFit?

CrossFit is a results-oriented fitness program with a focus on lifestyle changes through training.

The program’s workouts feature constantly varied, high-intensity and functional movements.

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Founded more than 20 years ago in a garage gym in Santa Cruz, California, CrossFit has since become one of the world’s most popular training programs for improving health and fitness performance.

CrossFit aims to help its members excel in various physical activities and challenges both inside and outside the gym.

How is CrossFit different from other fitness programs?

CrossFit is known for its workouts that blend elements from weightlifting, gymnastics and cardio.

The fitness company has more than 12,000 CrossFit affiliates spanning 146 countries, Austin Malleolo, senior director of strategy and operations of affiliates at CrossFit, told Fox News Digital.

“Our affiliates are staffed with trainers who are equipped to teach you how to move safely, effectively and efficiently,” Malleolo said. 

The CrossFit program is based on three pillars: variance, functionality and intensity.

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Variance is the practice of regularly changing workout routines and exercises. 

By incorporating a wide variety of movements, variance provides CrossFit members with a broader range of physical challenges. This approach exposes the body to different stimuli, which promotes continual growth and adaptation.

A CrossFit class is a one-hour group session led by a coach.

Functionality is doing exercises that mimic real-life activities. By building strength, flexibility, endurance and coordination through functional movements, members can better navigate daily activities outside the gym.

Intensity is the level of effort exerted during workouts. While the word may seem intimidating, it’s simply a guiding principle that symbolizes the importance of working hard to achieve tangible results.

What does a CrossFit class look like?

A CrossFit class is a one-hour group session led by a coach.

Typically, sessions begin with a whiteboard brief, where a coach outlines the workout flow, provides timing examples and demonstrates movements.

WE TRIED IT: CROSSFIT

Next, the coach discusses the goals of the workout, explaining the intended stimulus for members to understand the purpose behind the session. Scaling options are then provided for movements in the workout, allowing members to adjust based on their skill level.

CrossFit classes are designed to meet members at their current fitness levels and abilities. (CrossFit, LLC)

Physical activities begin with a general warm-up to get members moving and introduce movement patterns, followed by a specific warm-up tailored to the workout. The session’s main focus is devoted to the workout itself, where participants engage in the exercises outlined.

The session concludes with a cool-down, which incorporates stretching and mobility exercises to reduce muscle soreness. This approach allows members to receive a well-rounded workout experience.

How does CrossFit accommodate those with different fitness levels?

CrossFit classes are designed to meet members at their current fitness levels and abilities, Malleolo told Fox News Digital.

“Coaches start by tailoring the workout of the day to allow for all members in the class to achieve the intended goals of the workout that day by having a robust warm-up that allows the members to properly warm up and practice the movements that they will be doing in the workout,” Malleolo said. “The coach will adjust the loading, reps, and time of the workout based on the member’s needs to align with that day’s workout.”

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Throughout the class, coaches teach and refine movements, offering guidance to improve performance.

CrossFit promotes inclusivity and accessibility by accommodating those with a range of fitness levels, allowing participants to progress safely at their own pace.

Starting your fitness journey can feel overwhelming, but with the right support, it becomes a powerful step toward a healthier lifestyle. (CrossFit, LLC)

How do I start CrossFit?

Starting your fitness journey can feel overwhelming, but with the right support, it becomes a powerful step toward a healthier lifestyle.

“Trust that the hardest part is to walk through the front door of the gym,” Malleolo said. “Once you are there, you will be taken care of! No matter where you are in your fitness journey, a CrossFit Affiliate is designed to be a part of that journey, no matter where you are today.”

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You can begin the process by researching CrossFit locations near you and setting up an introductory session.

Many CrossFit facilities offer programs designed to teach newcomers the fundamental movements in a supportive environment, Malleolo told Fox News Digital.

The program can be challenging, but it should also be enjoyable as well. 

Participants are encouraged to embrace the process, celebrate their achievements and cherish the friendships made within the CrossFit community.

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