Many prefer grass-fed milk over conventional milk because of their added nutrition. But should you be cautious if you have high cholesterol?
Milk continues to be a favored drink option throughout the generations, and it is easy to see why. Whether stirred into coffee, paired with cereal, or enjoyed by the glassful, it is a versatile beverage that offers a range of nutrients1, providing calcium, protein, vitamins B2 and B12, vitamin A, vitamin D, potassium, and phosphorus. In fact, because of the nutrition that milk and other dairy products provide, the USDA2 recommends adults incorporate 3 cups of dairy into their diet each day.
One type of milk that has gotten quite the buzz lately is grass-fed milk. People often choose grass-fed milk for its nutritional benefits over conventional cow’s milk. But is grass-fed milk a smart choice for someone with high cholesterol?
What makes milk “grass-fed”?
Milk is considered grass-fed3 when it comes from cows fed mainly grass and other forage rather than grains or grain byproducts. According to the USDA4, forage includes grass, legumes, brassica (such as cabbage, cauliflower, turnips, and kale), browse (young shoots and twigs), and cereals in their pre-grain state. Grass-fed cows must also have access to pasture during the growing season.
Grass-fed milk is sometimes confused with organic milk. Though they are both chosen as healthier alternatives to conventional cow’s milk, they are not the same. Organic milk5 does not necessarily mean that the cows were fed exclusively on grass. Organic dairy cows can eat organic grain as well as organic forage, and they are not treated with any hormones or antibiotics.
Is grass-fed milk better?
What cows eat day-to-day affects the quality of their milk, and because grass-fed cows graze on nutrient-rich, fresh plants, grass-fed milk tends to be more nutritious3 than conventional milk in a few key ways.
For starters, grass-fed cows produce milk that has higher levels of omega-3 fatty acids, including alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), and docosapentaenoic acid (DPA). Omega-3 fatty acids6 are essential for human health and have many roles in the body, such as maintaining cell membrane structure and supporting brain and eye function. Omega-3s may also help prevent cardiovascular disease by reducing triglyceride levels and treat rheumatoid arthritis by lowering inflammation. It is recommended that adults get around 1600 mg of omega-3 fatty acid each day.
Evidence shows that grass-fed milk can have up to 3 times7 the amount of omega-3 fatty acid as grain-fed milk. One specific study8 looked at 1,163 US-wide samples of grass-fed and conventional milk over three years and analyzed their fatty acid content. The study compared the omega-3 fatty acid levels in 100 g of milk between grass-fed milk and conventional milk. Researchers found that the milk from grass-fed cows had 147% more total omega-3 fatty acids than conventional milk, offering 56.5 mg of total omega-3 compared to 19.8 mg of total omega-3.
Grass-fed milk also has lower levels3 of omega-6 fatty acids, including linoleic acid (LA) and arachidonic acid (AA). Omega-6 fatty acids are also essential nutrients for the body, but consuming them in a higher proportion9 relative to omega-3 fatty acids can lead to inflammation and cardiovascular disease. In addition, grass-fed milk has 2 to 5 times7 more conjugated linoleic acid (CLA), a type of fat with anti-inflammatory, anti-cancer, and heart-protective effects.
And because grazing cows mainly eat diverse nutrient-rich plants, their milk contains concentrated levels of beneficial phytochemicals7 that have antioxidant properties such as polyphenols, tocopherols, carotenoids, and terpenoids, which can protect against chronic disease by reducing oxidative stress and inflammation. Grass-fed milk can even have comparable levels of antioxidants to some plant foods. For example, experts7 found that there is a similar amount of polyphenols gallic acid and catechin between grass-fed milk (1.3 mg gallic acid/ 100 g and 4.3 mg catechin/ 100 g) and some green teas (1.2 mg gallic acid/100 g and 4.3 mg catechin/100 g).
Grass-fed milk also has a higher concentration of beta carotene3 than conventional milk. Beta carotene converts into an active form of vitamin A and has antioxidant properties essential for vision, immunity, and skin health. It gives fruits and vegetables their orange or yellow color, and it also adds a yellowish tint to grass-fed milk.
How does grass-fed milk influence cholesterol?
Grass-fed milk may offer some health perks over regular milk, but it does have its drawbacks. For example, whole grass-fed milk is typically higher in total saturated fat than regular whole milk. Below compares the nutritional profiles of one brand of grass-fed milk with regular milk.
The American Heart Association (AHA)12 does not have a specific recommendation for drinking grass-fed milk, but it does suggest that eating foods with saturated fats can cause your body to produce more harmful LDL-cholesterol in the blood. For this reason, it recommends sticking with 2 to 3 daily servings13 of fat-free or low-fat dairy products.
The AHA also recommends that people who need to lower their cholesterol reduce their saturated fat intake to less than 6%14 of their total daily calories. This amounts to around 11 to 13 g of saturated fat per day if following a 2000-calorie diet. So, at 9 grams per serving, having just one glass of whole grass-fed milk will provide almost an entire day’s worth of saturated fat.
When it comes to grass-fed milk’s actual effect on cholesterol, the research is sparse. Even with the nutritional boost from a lower omega-6 to omega-3 fatty acid ratio and higher amounts of CLAs, polyphenols, and antioxidants, it is difficult to predict how grass-fed milk impacts cholesterol. This is partly because not enough clinical studies have been conducted, and partly because the nutritional makeup of each glass of milk is influenced by factors3 aside from the cow’s diet. These factors include a cow’s breed, genetics, lactation stage, environmental conditions, and even the time of year. This variability can make it challenging to determine whether drinking grass-fed milk alone may reduce or increase cholesterol, and more clinical studies are needed.
The bottom line
Grass-fed milk is milk that comes from cows fed a forage-based diet. Unlike regular milk, which is produced from cows that feed on grain, grass-fed milk is typically more nutritious with higher omega-3 fatty acids, lower omega-6 acids, and more CLAs, phytonutrients, and antioxidants. However, grass-fed milk usually contains more saturated fat than regular milk. People who need to lower their cholesterol should aim for a saturated fat intake of less than 6%14 of daily calories. More research is needed to determine how drinking grass-fed milk affects cholesterol. In the meantime, follow a balanced diet15 that includes a variety of heart-healthy foods rich in fiber, antioxidants, and healthy fats, such as fruits, vegetables, nuts, seeds, fish, and olive oil. And if you would like to enjoy grass-fed milk, be sure to check the nutrition label, choose low-fat or skim13 options if possible, and be mindful of how much saturated fat you consume throughout the day.
Sources:
- https://www.hsph.harvard.edu/nutritionsource/milk/
- https://www.dietaryguidelines.gov/sites/default/files/2021-03/Dietary_Guidelines_for_Americans-2020-2025.pdf
- https://www.mdpi.com/2304-8158/8/8/350
- https://ask.usda.gov/s/article/What-is-grass-fed-meat
- https://www.ams.usda.gov/sites/default/files/media/Dairy%20-%20Guidelines.pdf
- https://ods.od.nih.gov/factsheets/Omega3FattyAcids-HealthProfessional/
- https://www.frontiersin.org/articles/10.3389/fsufs.2020.555426/full?__s=eay5yedy6egi8hj4lp7v
- https://onlinelibrary.wiley.com/doi/full/10.1002/fsn3.610
- https://openheart.bmj.com/content/5/2/e000946
- https://www.nutritionix.com/i/grass-root/grass-fed-only-whole-milk/62ab2ceeda82f10006653881
- https://www.nutritionix.com/food/whole-milk
- https://professional.heart.org/en/science-news/dietary-fats-and-cardiovascular-disease/Commentary
- https://www.heart.org/en/healthy-living/healthy-eating/eat-smart/nutrition-basics/dairy-products-milk-yogurt-and-cheese
- https://www.heart.org/en/health-topics/cholesterol/prevention-and-treatment-of-high-cholesterol-hyperlipidemia/the-skinny-on-fats
- https://www.mayoclinic.org/diseases-conditions/high-blood-cholesterol/in-depth/cholesterol/art-20045192
