What Are the Vascular Effects of Blueberries?
April 14, 2023BY AMY SYNNOTT
Packed with fiber, antioxidants, phytonutrients, and healthy fats, these nutritional powerhouses can help lower blood pressure, and reduce your risk of heart attack, stroke, and heart disease.
If you want to avoid hypertension—and associated cardiovascular crises like heart attack and stroke—take some advice from Hippocrates, the father of modern medicine, who famously said in 440 BC, “let food be thy medicine.”
While he may not have been familiar with the term “vascular superfoods,” Hippocrates obviously knew what he was talking about. Ever since 1978, when physiologist Ancel Keys published the seminal Seven Countries Study (the world’s first multi-country study showing the correlations between diet and coronary heart disease) study after study has shown that a high fiber, phytonutrient-rich diet composed mostly of whole, plant-based foods can dramatically lower your risk of cardiovascular disease and help control existing cardiovascular conditions like hypertension, high cholesterol, insulin resistance, and arterial stiffness.
Overall, people who eat a lot of fruits and vegetables (~500 g/day) have a 22% lower risk of cardiovascular disease than people with low intake (0-40 g/day), according to a 2020 review in The International Journal of Obesity Supplements.
To make shopping easier for you, we’ve put together a heart-healthy grocery shopping list that reflects the latest dietary guidelines for cardiovascular health released by the American Heart Association in 2021 (this free, downloadable cheat sheet can easily be synced with Amazon Prime, Instacart, and virtually any other grocery shopping app).
These cardiovascular superfoods are the MVPs of the Mediterranean diet and the Dash diet, two of the most popular heart-healthy diet plans out there.
1. Oats and barley: Whole grains like oats and barley contain beta-glucans, a type of soluble fiber that benefits heart health in many ways. In addition to lowering the body’s insulin response and boosting immunity, studies show that it can also lower cholesterol.
Other grains, such as rye, wheat and sorghum, contain beta-glucans but in smaller quantities than oats and barley. Seaweed, baker’s yeast and various species of mushrooms such as reishi and shiitake also contain beta-glucans.
Eating three grams of beta-glucans a day can reduce cholesterol by up to 15% and total cholesterol by nearly 9%, according to the latest research. “While oats have the most beta glucans of any food—one and a half cups of cooked oatmeal supplies three grams—you can get the required dose by combining several different foods with less amounts throughout the day,” says Preventive Cardiology dietitian Michelle Routhenstein, MS, RD, CDE, CDN at EntirelyNoourished.com. For example, add a tablespoon of oat bran to your morning smoothie, then eat ½ cup of cooked barley for lunch or dinner.
2. Wild salmon. Fatty fish like salmon, mackerel, and sardines, are an excellent source of long-chain omega-3 fatty acids. Studies show these unsaturated fats prevent heart attacks by helping the heart maintain its rhythm. They also make blood less likely to clot, lower blood pressure, keep blood vessels healthy and less likely to narrow, reduce triglycerides and lower inflammation, according to the latest research.
Salmon has the most long-chain omega-3s, so the American Heart Association recommends adding a 3½-ounce serving to your diet at least two times a week. Be sure to choose wild salmon as farm salmon is often contaminated with PCBs and other toxins.
3. Dark leafy greens. Dark leafy greens like spinach, kale, and collard greens are loaded with anti-inflammatory vitamins, minerals, and fiber. They are also a good source of nitrates, which have been shown to reduce blood pressure. “Ideally, you want to be eating one to two servings a day,” says Routhenstein, noting that one serving is equal to one cup of raw greens or a half cup cooked.
4. Unsalted seeds and nuts. A good source of cholesterol-friendly unsaturated fats and fiber, unsalted nuts like almonds, walnuts, hazelnuts and pecans contain high amounts of potassium, magnesium and other minerals known to reduce blood pressure. Studies have shown that eating a handful of nuts or seeds per day can help reduce the risk of cardiovascular disease. Walnuts, chia seeds and flax seeds also offer heart-healthy omega-3 fatty acids. Routhenstein recommends adding a tablespoon of these omega-rich seeds to a meal or snack, shooting for a total of three to five servings of nuts and seeds per week.
5. Pistachios. While modest portions of all unsalted nuts can benefit heart health, pistachios may be the healthiest in regulating blood pressure.Studies show pistachios can reduce peripheral vascular resistance (tightening), as well as lower heart rate, blood pressure and cholesterol. A single helping a day—one ounce or about 49 kernels—was better at lowering blood pressure than two helpings, according to one study. Nuts are highly caloric, so sticking with one serving a day will also help you maintain a healthy weight.
6. Beans and legumes: An excellent source of soluble fiber and blood sugar-stabilising protein, beans help reduce cholesterol levels, while helping to maintain a healthy weight by keeping you feeling full longer. A good source of fiber, gut-friendly prebiotics, protein, vitamins, and minerals, beans also help reduce inflammation and protect against cardiovascular disease. Canned varieties are typically high in sodium, so it’s far healthier to soak raw beans overnight before cooking them. If you must use canned, make sure to rinse beans before using them.
7. Low or non-fat yogurt. Though dairy consumption remains a hotly contested topic in nutrition circles, studies show low fat dairy consumption is associated with a lower risk of all forms of mortality, CVD and obesity, according to the AHA. If you are not lactose intolerant, Routhenstein recommends adding fermented, non-sweetened, non-fat greek yogurt to your diet. In addition to protein and calcium, yogurt contains probiotics, which can help gut microbiota (thus improving inflammatory conditions like atherosclerosis and hypertension). Some studies also suggest that whey protein improves insulin response, and reduces cholesterol, blood pressure and arterial stiffness (rigid artery walls that experts believe are an early biomarker for cardiovascular disease).
8. Avocados: Avocados are a good source of healthy unsaturated fats, fiber, and vitamins C, E, and K. According to a 2022 study published in the Journal of the American Heart Association, heavy avocado consumers (≥2 servings/week) had a 16% lower risk of CVD and a 21% lower risk of coronary heart disease compared to people who ate none. This same study showed that substituting half a serving/day of margarine, butter, egg, yogurt, cheese, or processed meats with the same amount of avocado was correlated with a 16% to 22% lower risk of CVD.
9. Tomatoes: Tomatoes are an excellent source of the antioxidant lycopene. Lycopene is a phytonutrient that has been shown to reduce the risk of cardiovascular disease. Tomatoes are also a good source of vitamins A and C, as well as fiber. The antioxidants in tomatoes become more bioavailable when you cook them so you are better off adding some marinara to your spiralized zucchini noodles than tossing raw ones in your lunchtime salad. Routhenstein also mentions that lycopene is found in watermelon and red bell peppers, which don’t need to be cook
10. Low-sugar berries: High in fiber, vitamins C and E, brightly colored berries like strawberry, raspberry blackberry and pomegranate contain phytonutrients that reduce inflammation throughout the body. A 2019 study published in the American Journal of Clinical Nutrition found that eating one cup of blueberries a day reduced arterial stiffness and increased levels of HDL (the “good” cholesterol). The researchers estimated that it reduced the risk of coronary heart disease by 11.4 to 14.5%. Interestingly, no such improvement was observed in people who consumed only ½ cup of blueberries, so don’t be shy about loading up that Vitamix!
11. Whole grains: Withsoluble and insoluble fiber, B vitamins, minerals, and phytonutrients, whole grains have been shown to reduce the risk of cardiovascular disease, as well as improve cholesterol levels and blood sugar control. If you are sensitive to gluten, consider quinoa. High in fiber, protein, vitamins, and minerals, quinoa has been shown to improve cholesterol levels, reduce inflammation, and protect against cardiovascular disease and diabetes.
12. Olive oil: Unlike tropical oils like coconut, palm or palm kernel which contain dangerous trans fats, cold-pressed virgin olive oil offers healthy fats and antioxidants that improve cholesterol levels, reduce inflammation, and protect against cardiovascular disease.
13. Garlic: High in vitamin C, B6, and allicin, a compound which has been shown to reduce cholesterol levels and blood pressure, garlic is also a great source of prebiotics, indigestible fiber that—along with probiotics—promotes a healthy microbiome, which reduces inflammation.
14. Green tea: Studies show plant-based compounds called catechins in green tea can reduce cholesterol and protect against cardiovascular disease, according to a 2015 meta-analysis in the International Journal of Cardiology. One word of caution: Green tea is best consumed in your daily diet, as there is some evidence that high dose supplements may be toxic to your liver, especially when consumed in complex formulations that combine green tea with other potentially hepatotoxic compounds.
15. Beets: Beets and beetroot juice increase levels of nitric oxide, which has a vasodilatory (widening) effect on blood vessels, lowering blood pressure. Beets can also reduce inflammation in blood vessels in people with coronary heart disease, according to a June 2022 report from the British Heart Foundation. One easy way to add beets to your diet: Whip up a smoothie with ½ cup beetroot juice, 1 cup nonfat Greek yogurt, 1 cup frozen berries and a generous chunk of fresh ginger. The ginger helps mask the earthy flavor of the beetroot juice.
16. Soybeans: A good source of plant protein, vitamins, minerals, and fiber, soybeans (including edamame and tofu) have been shown to reduce the risk of cardiovascular disease, as well as improve cholesterol levels and blood sugar control.
17. Dark chocolate: Studies show epicatechin, a flavanol found in dark chocolate may help reduce blood pressure, cholesterol, and inflammation. A Dutch study involving more than 55,000 people showed that just two to six ounces of cocoa per week also lowered the risk of developing an irregular heartbeat—a condition that dramatically increases your risk of having a stroke—by 20%. Keep in mind: milk chocolate does not contain much of this key cardiovascular flavanol so make sure you choose dark chocolate with at least 70% cacao. Also, chocolate is high in calories and saturated fat so stick with a modest portion (an ounce or two per day).
SOURCES
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Pacheco LS, Li Y, Rimm EB, Manson JE, Sun Q, Rexrode K, Hu FB, Guasch-Ferré M. Avocado Consumption and Risk of Cardiovascular Disease in US Adults. J Am Heart Assoc. 2022 Apr 5;11(7):e024014. doi: 10.1161/JAHA.121.024014. Epub 2022 Mar 30. PMID: 35352568; PMCID: PMC9075418.
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Pang J, Zhang Z, Zheng TZ, Bassig BA, Mao C, Liu X, Zhu Y, Shi K, Ge J, Yang YJ, Dejia-Huang, Bai M, Peng Y. Green tea consumption and risk of cardiovascular and ischemic related diseases: A meta-analysis. Int J Cardiol. 2016 Jan 1;202:967-74. doi: 10.1016/j.ijcard.2014.12.176. Epub 2015 Jan 4. PMID: 26318390.