Omega-3 fatty acids are highest in milk labeled as organic grass-fed

 — When you pick up a gallon of milk at the store, the nutrients it contains may depend on both what’s on the label and the time of year. A new study reports that omega-3 fatty acids are highest in milk labeled as organic grass-fed and lowest in conventionally-produced milk. Other fatty acids varied by dairy production method and season.

“These findings contribute to a greater understanding of the role that production systems may play in determining the nutritional composition and potential nutritional value of milk,” said Emily Youngmark, MS, a PhD student at the University of Vermont. “The observed differences in fatty acid composition may represent one factor consumers consider when choosing milk products.”

Youngmark will present the findings at NUTRITION 2026, the flagship annual meeting of the American Society for Nutrition, held July 25-28 in National Harbor, Maryland, just outside Washington, D.C. Youngmark conducted the study with Jana Kraft, PhD, associate professor at the University of Vermont.

U.S. consumers can often find a large array of options in the dairy aisle, but the differences among them are not always clear. Since products marketed as organic, grass-fed or pasture-based are often sold at premium prices and promoted as having nutritional advantages, the researchers sought to find out whether production systems actually influence milk composition.

Over the course of a year, the team collected over 300 samples of milk sold by retailers across Vermont and New York. Using information from dairy producers and product labels, they categorized each sample as conventional (63 samples), organic (111), organic grass-fed (91) or non-organic, pasture-based (40).

On average across all seasons, organic grass-fed milk contained significantly more omega-3 fatty acids than all other milks, providing 88 milligrams per serving compared with 25 mg/serving in conventionally-produced milk. By contrast, omega-6 fatty acids were highest in conventionally-produced milk, which contained 166 mg/serving versus 92 mg/serving in organic grass-fed milk. While both types of fatty acids are part of a healthy diet, experts recommend focusing on increasing omega-3 intake, which is linked with a reduced risk of heart disease, type 2 diabetes and inflammation.

The fatty acid composition of non-organic, pasture-based milk was generally comparable to organic milk, with some seasonal variation. In general, it appears that cows with more access to pasture and fresh forage produce milk with more beneficial fatty acids. Variation in nutritional composition throughout the year likely results from seasonal differences in forage quality.

Although the results revealed significant differences in fatty acid composition among milk samples, researchers noted that the health implications of these differences remain uncertain. Further studies would be needed to determine whether regularly consuming certain types of milk leads to measurable improvements in health outcomes.

“It is important to put these findings in perspective. While the differences we observed may be nutritionally relevant, they are unlikely to produce major health effects on their own. Rather, the fatty acid composition of organic grass-fed milk may contribute as one component of an overall healthy dietary pattern and lifestyle,” said Youngmark.

Conventional milk has no formal definition but generally refers to milk produced from intensively managed dairy systems. Certified organic milk is produced under federally regulated standards that prohibit the use of pesticides, genetically modified feeds and most synthetic additives and require pasture access for at least 120 days per year. Organic grass-fed certification imposes additional requirements, including pasture access for at least 160 days per year and the exclusion of grain products from feed. The term “pasture-based” can appear on both organic and non-organic milk; non-organic, pasture-based milk production systems emphasize pasture access but are not certified organic. 

A daily multivitamin may help older adults maintain functional health

 

The ability to perform everyday activities free of debilitating symptoms profoundly affects quality of life as we age. In a new study, older adults who took a daily multivitamin had significantly better measures of functional health after 3 years compared with those who took a placebo.

According to researchers, the findings suggest a daily multivitamin can help older people maintain day-to-day functioning by helping to preserve cognitive abilities, and it may also benefit blood circulation and physical stamina.

“What makes this work unique is our focus on functional health, how people actually feel and function in their daily lives—rather than just the prevention of major diseases,” said Bayu B. Bekele, PhD, a postdoctoral fellow at the Georgia Prevention Institute of the Medical College of Georgia at Augusta University. “For older adults, these findings suggest that a daily multivitamin could be a helpful, low-risk addition to a healthy lifestyle to support physical well-being as they age, although it is not a substitute for a good diet or exercise.”

The researchers analyzed data from over 16,000 people aged 60 years and older who participated in the COcoa Supplement Multivitamins Outcomes Study (COSMOS). COSMOS participants were randomly assigned to take a daily multivitamin, a cocoa extract supplement, both or neither, with placebos used for the control group and for those taking only one supplement.

After 3 years, participants taking a multivitamin had significantly better functional health than those taking a placebo based on their responses to the Kansas City Cardiomyopathy Questionnaire. The greatest differences were seen in symptom burden and clinical summary score, which reflects an average of symptom burden and physical ability scores. 

“Multivitamin use supporting heart health and overall physical function may help maintain the ability to perform everyday activities such as dressing, bathing, walking, climbing stairs, jogging or hurrying, and completing household chores. These benefits may be particularly relevant for individuals experiencing fatigue, shortness of breath or swelling in the feet, which can limit daily functioning,” said Bekele.

Cocoa extract did not significantly change functional health scores in the overall population, although it provided a significant benefit in the patients with congestive heart failure.

It is important to check with a doctor before taking any new supplements.

Is your diet driving up your cholesterol? That may depend on your gene

 

Study suggests genetic factors explain why some people see their LDL cholesterol spike on a low-carb, high-fat diet

Can a low-carb diet cause your cholesterol to skyrocket? This question has vexed researchers and influencers alike as the popularity of low-carbohydrate diets has surged, yet the evidence has remained mixed. New research suggests that the answer depends on your genes.

According to the study, the high saturated fat intake that tends to accompany a low-carb diet interacts with genetic factors in ways that can increase low-density lipoprotein (LDL) cholesterol, considered a key driver of heart disease risk. The role of genes explains why different individuals can follow the same diet but see different outcomes. 

“Our findings suggest that some individuals may be more sensitive to the LDL cholesterol-raising effects of saturated fat, particularly in the context of a low-carbohydrate diet, because of their genetic background,” said Alexa Barad, PhD, RDN, a postdoctoral scholar at Stanford University School of Medicine.

“These findings highlight that there is real heterogeneity in how people respond to diet. Dietary conversations can sometimes become overly simplified. One person may say, ‘Low-carb diets always raise LDL cholesterol,’ while another says, ‘My LDL cholesterol did not change at all.’ Our findings suggest that both experiences can be true, depending, at least in part, on the individual’s genetic makeup,” said Barad.

Previous studies have shown healthy low-carbohydrate diets can support weight loss and blood sugar control for some people, but these diets have inconsistent effects on LDL cholesterol. Researchers sought to find a way to predict who would likely benefit from a low-carb diet and who may see a dangerous spike in LDL cholesterol.

The research is based on data from DIETFITS, a randomized controlled trial in which over 600 adults followed either a healthy low-carb or healthy low-fat diet for a year. The primary study found that neither diet was superior to the other in terms of weight loss. For the new analysis, researchers assessed the relationships among genotype, saturated fat intake, diet type and change in LDL cholesterol from baseline to 6 months in 431 DIETFITS participants with available genetic data.

Among participants following the low-carb diet, the results showed that those with a genetic predisposition toward elevated LDL cholesterol were more likely to see their cholesterol rise. The results also showed that this was driven by a greater sensitivity to saturated fat, meaning that people at higher genetic risk had the largest increases in LDL cholesterol when they consumed more saturated fat. People following a low-fat diet did not show the same patterns.

Unlike prior studies, which have mostly focused on single genetic variants, researchers combined thousands of genetic variants across the genome (creating what is known as a polygenic score) to estimate each participant’s overall tendency for higher or lower LDL cholesterol. In the future, Barad said clinicians could potentially use polygenic scores to help identify people who are more likely to experience adverse LDL cholesterol responses to certain dietary modifications.

However, even without genetic testing, the study offers an important lesson that the response to diet can vary from person to person, underscoring the need to monitor how your body is responding to a dietary change rather than assuming the results will be the same for everyone, Barad added.

Further studies could help to confirm the findings and ensure they apply broadly to diverse populations. General dietary guidance suggests limiting saturated fat to less than 10% of daily calories and favoring unsaturated fats. For those choosing a low-carbohydrate diet, emphasizing healthier fat sources such as nuts, seeds, olive oil and avocado over foods high in saturated fat such as butter, beef tallow, fatty cuts of meat and processed meats may help reduce the risk of adverse cholesterol responses, Barad noted.

Prebiotic sodas typically contain as much sugar as fiber

While healthier than regular sodas and fruit drinks, prebiotic sodas do not necessarily compare favorably with other alternative

 Prebiotic sodas have become more popular in recent years, with a wave of new products promising gut health benefits and low-calorie enjoyment. According to a new analysis, however, many of these beverages contain relatively little prebiotic fiber content and more sugar than marketing claims might imply.

“Many products include nutrition and functional claims that may overstate their nutritional quality. For example, some labels claim ‘no added sugar,’ yet the product may still contain around 10 grams of total sugars from sources like juice,” said Carlos R. Soto Díaz, MPH, a PhD candidate at the University of North Carolina at Chapel Hill. “This raises concerns that such claims may create a ‘health halo,’ leading consumers to believe the product is healthier than its overall nutritional profile suggests.”

Prebiotic sodas represent one of the fastest growing beverage segments in the U.S. market, with estimated sales of $777 million in 2025. Using data from the Mintel Global New Products Database, researchers analyzed 108 prebiotic sodas launched in the U.S. between 2021-2025.  These were defined as carbonated beverages that contain fiber and use the term “prebiotic” in the product name, package claims or ingredient lists. They compared prebiotic sodas’ nutritional contents to regular sodas, diet sodas, fruit drinks and flavored sparkling waters introduced during the same time period.

On average, prebiotic sodas contained about 35 calories, 5 grams of sugar and 5 grams of fiber per 12-ounce can. In terms of calories and sugar, they ranked lower than regular sodas and fruit drinks but higher than diet sodas and flavored sparkling waters. In addition, nearly two-thirds of prebiotic sodas contained non-nutritive sweeteners such as stevia. By comparison, over 90% of diet sodas contained non-nutritive sweeteners, while less than 28% of fruit drinks, 16% of flavored sparkling waters and 12% of regular sodas contained them.

Prebiotic sodas consistently contained more fiber than other beverages, ranging from about 2 to 9 grams of fiber per can. In the U.S. market, the term “prebiotic” is not tied to a specific amount of fiber, so researchers cautioned that consumers should not assume a product contains a meaningful amount simply because it is labeled as prebiotic, and sodas should not be relied upon as a primary source of dietary fiber.

“I would encourage consumers not to be swayed by marketing claims and to carefully review the Nutrition Facts label,” said Soto Díaz. “While certain types of prebiotic fibers have been shown to support gut health, the extent to which the amounts found in these beverages provide meaningful benefits is still unclear. Any potential benefits should be considered alongside the product’s overall nutritional profile, including calories, sugars and non-nutritive sweeteners.”

When considering the healthfulness of prebiotic sodas, the researchers say it is important to consider what they are replacing. For people who regularly consume sugary beverages, switching to prebiotic sodas could help to reduce overall calorie and sugar intake. On the other hand, switching to prebiotic sodas might not be as beneficial for people who typically choose low- or no-calorie beverages.

Plant-forward planetary health diet linked to lower heart disease risk

 A 20-year study of more than 65,000 postmenopausal women found that higher adherence to the Planetary Health Diet was associated with a lower risk of overall cardiovascular disease, coronary heart disease, stroke and heart failure.

The findings showed that women whose diet most closely followed the Planetary Health Diet had about a 28% lower risk of cardiovascular disease compared with women in the group scoring the lowest for adherence. However, even moderate adherence to the diet was linked with lower risk.

The Planetary Health Diet emphasizes foods such as fruits, vegetables, whole grains, legumes, nuts and unsaturated fats while limiting foods such as red and processed meats, added sugars, refined grains and saturated fats.

“Our results suggest that people may not need to follow a perfect or very restrictive diet to see potential heart-health benefits,” said Donya Shahamati, a doctoral student in public health at the University of California, Irvine. “This is especially important for postmenopausal women, because cardiovascular risk increases with age and tends to rise after menopause.”

“Moving toward a more plant-forward, higher-quality diet can be accomplished through small, realistic changes,” said Shahamati. “These changes might include filling half the plate with vegetables more often; using avocado or olive oil in place of butter; choosing oatmeal or whole-grain cereal for breakfast; or trying a meatless meal once per week.”

For the new research, the investigators followed 66,892 participants in the Women’s Health Initiative (WHI), a long-term national health study funded by the National Heart, Lung and Blood Institute at the National Institutes of Health. All the women included in the analysis were free of cardiovascular disease at the start of the study (1994-1998) and had complete information on diet and other important health and lifestyle factors.

Using information collected through a food frequency questionnaire administered at the beginning of the study, the researchers calculated a Planetary Health Diet Index score for each study participant, with higher scores indicating a diet was more aligned with the Planetary Health Diet. The researchers then divided the women into five groups based on how closely their diets aligned with the Planetary Health Diet.

The women, who were around 63 years old at the start of the study, were followed for about 20 years to see who developed cardiovascular disease. When analyzing the data, the researchers adjusted for several factors that could affect cardiovascular risk, including age, race and ethnicity, education, income, smoking, alcohol intake, physical activity, body mass index and total calorie intake.

“We did not only look at overall cardiovascular disease,” said Shahamati. “We also looked separately at coronary heart disease, stroke and heart failure. This helped us see whether the pattern was similar across different types of cardiovascular outcomes.”

Overall, the results showed that women in the group whose diets were more closely aligned with the Planetary Health Diet had the lowest risk of cardiovascular disease. These women also showed a decreased risk of heart disease, heart failure and stroke risk compared to the women in the lowest-adherence group.

However, even moderate adherence to the diet was associated with a decrease in risk, with each 10-point increase in Planetary Health Diet Index score linked to further risk reduction.

The researchers caution that an observational study like this cannot show that diet directly caused the lower risk in women.

Which vaccines the CDC recommends during pregnancy

 

 Most Americans are unaware or unsure of which vaccines the Centers for Disease Control and Prevention (CDC) recommends during pregnancy, according to a nationally representative survey of U.S. adults by the Annenberg Public Policy Center (APPC) of the University of Pennsylvania.

Almost half of those surveyed know that the CDC recommends getting the seasonal flu vaccine during pregnancy, while less than a third know that the CDC recommends the Tdap (tetanus, diphtheria, and pertussis), RSV (respiratory syncytial virus), and hepatitis B vaccines if one is not up to date on these vaccinations.

For the Covid-19 vaccine, over half of those surveyed do not know whether the CDC recommends it during pregnancy. While the CDC says that the vaccine helps reduce the risk for severe illness from Covid-19, it does not explicitly say the vaccine is recommended. Instead, the CDC says its Covid-19 vaccine recommendations are “now based on individual decision making, which emphasizes considering the benefits and risks of vaccination.”

Women of childbearing age (ages 18-49) are significantly more knowledgeable than other adult groups about most of the CDC’s pregnancy vaccine recommendations, although many in this group are also not sure what is recommended.

Uncertainty is a dominant finding in this survey. For each of four vaccines the CDC recommends during pregnancy, at least 45% of respondents are not sure whether the CDC recommends it.

The findings come from an APPC survey conducted on the research company SSRS’s Opinion Panel Omnibus platform among 1,031 U.S. adults from July 1-5, 2026. For further details, download the topline or see the end of this release.

“Our findings suggest that many Americans do not know which vaccines are recommended during pregnancy,” said Ken Winneg, APPC’s managing director of survey research. “The encouraging news is that relatively few people think that the CDC recommends vaccines that are not advised during pregnancy. The challenge is overcoming the widespread uncertainty over what the CDC does recommend.”

CDC recommendations during pregnancy

According to CDC guidance, four vaccines routinely recommended during pregnancy include:

• Seasonal influenza vaccine during flu season.
• Tdap vaccine during every pregnancy, preferably between 27 and 36 weeks’ gestation.
• RSV vaccine during weeks 32-36, administered during RSV season, which is September through January in most of the continental United States. Additional doses are not recommended during subsequent pregnancies.
• Hepatitis B vaccination for individuals who have not already been vaccinated.

The CDC says: “Covid-19 vaccination offers the greatest benefit if you are at higher risk for severe illness, including if you are pregnant. Pregnancy increases your risk of becoming very sick from Covid-19.” It adds that if you get sick with Covid-19 during pregnancy, you are at increased risk of complications that can affect your health and the health of your baby. The CDC recommends that Covid-19 vaccination decisions be made through individual decision making after considering the benefits and risks.

Other medical professionals more clearly back the Covid-19 vaccine during pregnancy. The American College of Obstetricians and Gynecologists (ACOG) strongly recommends that pregnant individuals be vaccinated against Covid-19 and “continues to recommend that all pregnant and lactating individuals receive an updated COVID-19 vaccine or ‘booster.’”

Awareness of recommended vaccines is low

Survey respondents were asked whether the CDC recommends each of eight vaccines during pregnancy. In addition to the five vaccines noted above, respondents were asked about three vaccines the CDC does not recommend during pregnancy: MMR or measles, mumps and rubella; chickenpox or varicella; and human papillomavirus or HPV.

Among U.S. adults overall, about a quarter to less than half of adults correctly identify any of the CDC-recommended vaccines, with the fewest (23%) knowing that the CDC recommends the hepatitis B vaccine during pregnancy and the most (48%) knowing the seasonal flu vaccine.

With the exception of RSV, women age 18 to 49 are significantly more likely than other groups (all adult men and women over 49 years old) to correctly identify all of the CDC-recommended vaccines. Among women 18 to 49, the vaccine least known to be recommended during pregnancy is the hepatitis B vaccine (30%) and the most known is the seasonal flu vaccine (60%).

Uncertainty dominates

For most of the vaccines, the most common response to whether the CDC recommends it during pregnancy is “not sure.” For each of the four recommended vaccines and the Covid-19 vaccine, from 45% to 66% of the overall adult population was not sure whether these were recommended. Among women of childbearing age, from 32% to 58% were not sure for each of the vaccines.

Few incorrectly think non-recommended vaccines should be taken

Current CDC guidance advises against administering the MMR and chickenpox vaccines during pregnancy because they are live-virus vaccines. The MMR and chickenpox vaccines should be given only before or after pregnancy. HPV vaccination is not recommended during pregnancy and should be delayed until after pregnancy if needed.

The survey found that relatively small groups of people incorrectly think that CDC recommends these vaccines:

• 21% say the CDC recommends the MMR vaccine during pregnancy.
• 17% say the CDC recommends human papillomavirus (HPV) vaccination.
• 17% say the CDC recommends chickenpox (varicella) vaccination.

Women of childbearing age are no more likely than others to incorrectly identify these vaccines as recommended. For the HPV vaccine, for example, 20% of women 18-49 years old incorrectly say it is recommended during pregnancy, compared with 16% of others, which is not a statistically significant difference.

For all three of these vaccines, the bigger issue is that a majority of respondents are not sure whether the CDC recommends that they should or should not be taken during pregnancy.

“Many Americans routinely get their immunizations from their primary healthcare providers or at local pharmacies, said Patrick E. Jamieson, director of APPC’s Annenberg Health and Risk Communication Institute, which oversees the health surveys. “It is critical that those professionals pay special attention to vaccine recommendations for recipients who are pregnant.”

Collagen peptides support bone health for female runners

 

Collagen is a protein found in skin, hair, nails, tendons, cartilage, and bones.

Our bodies naturally produce collagen using the foods we eat. But, in recent years, collagen peptides have gained popularity as a supplement to support joint, hair, skin, and gut health.

A new study led by Jennifer Fields, assistant professor of nutritional sciences in the College of Agriculture, Health and Natural Resources (CAHNR), provides evidence in favor of yet another application for collagen peptides – protecting female runners’ bones.

The study was published in Frontiers in Nutrition.

Bone health is a significant concern for endurance runners because, by the nature of their sport, they are consistently putting significant strain on their bones.

By putting stress on the bones, running activates osteoclasts to break down damaged bone. If a runner is, intentionally or not, not consuming enough calories, the osteoblasts that create new bone don’t have the fuel they need to rebuild the bone properly. This can lead to injury and long-term conditions like osteoporosis.

“Oftentimes, we associate running with being bad for us, bad for our bones, because runners are at a higher risk of stress-related injuries,” Fields says. “But oftentimes, it’s due to just simply under fueling and not giving your body enough calories to support training and recovery and adaptation.”

This is particularly relevant for female runners due to how the bone remodeling cycle interacts with hormones. Insufficient caloric intake lowers estrogen and progesterone levels, which in turn leads to increased bone breakdown and reduced bone formation.

Fields decided to study if collagen peptides could help intervene in this process, given that 90-95% of the organic bone matrix is comprised of collagen.

Collagen peptides are “incomplete amino acids.” Unlike complete amino acids, they do not trigger a response in our muscles. Instead, because of their unique structure (a repetitive pattern of three amino acids), they can trigger osteoclast and osteoblast activity.

“Unlike most dietary proteins, some of the dipeptides and tripeptides that make up collagen peptides can be absorbed intact by our intestine,” Fields says. “Those di- and tripeptides are what can potentially act on these osteoblast and osteoclast pathways to trigger a better bone turnover response where we’re favoring more bone formation.”

In this pilot study, Fields and her collaborators found that collagen peptides did indeed improve bone turnover. Looking at biomarkers in participants’ blood, the researchers saw that markers associated with bone formation increased and inflammation decreased in the group that took the collagen peptide supplements.

“We’re seeing some good preliminary data to show that four weeks is sufficient to move some of those acute biomarkers,” Fields says.

Other studies had looked at collagen peptides for bone health in postmenopausal women. Research on premenopausal women, on the other hand, has been extremely limited, and no one had looked at female runners specifically, despite their elevated risk of impaired bone remodeling and heightened risk of bone stress injuries.

Women’s bone density is generally not checked until after they enter menopause. But about 90% of bone mass develops by 18 and the remaining 10% by age 30. This means supporting bone health in young women is critical to ensuring their lifelong health and wellness.

“If we can target the premenopausal population and identify individuals who might be at risk of maladaptive bone responses, then hopefully we can reverse it and prevent early-onset osteopenia and osteoporosis,” Fields says.

Collagen peptides also have known benefits for hair, skin, joints, and gastrointestinal health, meaning incorporating them into the diet can have a host of benefits beyond bone health.

“What’s great about collagen peptides is that they’re universal,” Fields says. “It’s not a supplement where we’re only expecting one outcome. It can be incorporated into the diet as a supplement to help with some of these other health benefits.”

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Journal

Frontiers in Nutrition

DOI

10.3389/fnut.2026.1825906