You will be happy to know that the best fats for your cardiovascular health come in a variety of flavors and can be used in so many delicious dishes. The best fats are literally nutritional powerhouses you will find in nuts, seeds, avocados, and olives. Although tree nuts are high in fat, they contain fiber, high-quality protein, potassium, magnesium, folic acid, anti-inflammatory compounds, and antioxidants. Many nuts are also rich in omega-3 fatty acids. Nuts are rich in L-arginine, an amino acid that helps preserve the flexibility of arteries and discourage undesirable clotting. Predominately the fats in nuts are composed of healthy monounsaturated and polyunsaturated fatty acids.
Which Fats Reduce Risk for Cancer and Cardiovascular Disease?
Spanish researchers examined the effect on the primary prevention of cardiovascular disease of over 7000 older people (ages 55 to 90) randomized to a Mediterranean Diet, supplemented with extra virgin olive oil or nuts, and compared to a control group following a low fat diet. Here are their findings:1
- There were fewer people with type 2 diabetes or people taking medicine for hypertension in the group of people who ate the most nuts.
- Nut eaters had a 39% lower mortality risk and walnut eaters did even better at 45% lower risk.
- People eating more than 3 servings (1 serving — 28 g) a week of tree nuts reduced the risk of death due to cardiovascular disease by 55% and cancer by 40%. A similar effect was demonstrated with walnuts.
Three Ways Nuts Benefit Diabetics
Improve Vascular Health
In diabetes the ability of the blood vessels to dilate is significantly compromised. Stress also causes blood vessels to constrict. Two servings of pistachios per day lowered vascular constriction during stress and improved neural control of the heart in diabetic adults. In this study, one group of participants ate a standard heart-healthy diet, 27 percent fat and 7 percent saturated fat, while another group consumed a diet containing two servings of pistachios per day, about 3 ounces or 20 percent of calories from pistachio nuts. The typical research participant consumed about 150 pistachio nuts per day. The pistachio diet contained 33 percent fat and 7 percent saturated fat. At the end of each four-week diet period, the researchers measured blood pressure and total resistance to blood flow at rest and during two stress tests: a cold water challenge and a confusing mental arithmetic test. After the pistachio diet, blood vessels remained more relaxed and open during both the stress tests (even though the participants felt angry and frustrated during the math stress test).2
Lower Elevated Blood Cholesterol and Hemoglobin A1c
Jenkins and his colleagues found that nuts were useful in replacing some carbohydrate in diabetic individuals. They provided three different diet supplements to subjects with type 2 diabetes. One group was given muffins; the second group was provided with a daily two ounces of assorted nuts including raw almonds, pistachios, walnuts, pecans, hazelnuts, peanuts, cashews, and macadamias; and the third group was given a mixture of muffins and nuts.
The results? Participants receiving the nut-only supplement reported the greatest improvement in blood glucose control using the glycosylated hemoglobin (HbA1c) test. This lab test shows the average level of blood sugar (glucose) over the previous 3 months. Not only did nut diet consumers reduce their HbA1c, they also experienced a reduction in LDL cholesterol (“bad cholesterol”). Participants provided the muffin supplement or the mixed muffin-and-nut supplement experienced no significant improvement in blood sugar control. Those receiving the muffin-nut mixture also significantly lowered their serum LDL levels (“bad cholesterol”). What is also encouraging is that the nut group experienced no weight gain!3
Almonds Pack a Punch!
Almonds are particularly helpful for diabetic individuals. Regular, daily almond consumption reduces hemoglobin A(1c) in individuals with well-controlled type 2 diabetes mellitus.4 Inclusion of almonds in the breakfast meal decreased blood glucose concentrations and increased satiety, both acutely, and even after a second meal in adults with glucose intolerance.5
Nuts Help Obese Individuals?
Several cross-sectional analyses have shown an inverse association between higher nut consumption and lower body weight. Other types of studies found that increasing nut consumption was associated with lower weight gain over relatively long periods of time.6
Metabolic syndrome is a condition characterized by three of the following: excess visceral fat (pot-belly), insulin resistance, elevated blood pressure, elevated triglycerides, and low HDL level. Inflammation, increased risk for undesirable clotting, and increased sympathetic nerve activity contribute to the cardiovascular complications from metabolic syndrome. In obesity and metabolic syndrome, the ability of the blood vessels to dilate is impaired. Daily ingestion of 56 g of walnuts (approximately 1/4 cup) improves endothelial function in overweight adults with visceral adiposity. The addition of walnuts to this diet does not lead to weight gain.7
Nuts Help Appetite Control
Serotonin is a compound that helps transmit nerve signals, promotes a positive outlook and self-control, and decreases feelings of hunger. Just one ounce of mixed nuts (raw unpeeled walnuts, almonds, and hazelnuts) increased the serotonin level in individuals who had metabolic syndrome.8
Because of their high fiber and substantial fat content nuts can act as appetite suppressants. Here, though, Korean pine nuts might be your best bet for now because in one small study pine nuts stimulated two well-known appetite suppressing hormones (cholecystokinin and glucagon-like peptide) in overweight women. These women reported significantly less desire to eat only 30 minutes after ingestion compared with an olive oil placebo. A significant increase in cholecystokinin of 60% and glucagon-like peptide-1 of 25% remained as long as four hours after ingestion.9
Regular Consumption of Nuts Helps Chronic Diseases
Inflammation fuels chronic diseases such as obesity, diabetes, metabolic syndrome, and atherosclerosis. Regular consumption of nuts is associated with significant reduction of three pro-inflammatory markers.10 A study of 987 diabetic women showed a direct association between nut consumption and increased plasma levels of adiponectin,11 an important hormone that exerts anti-inflammatory properties. Adiponectin also helps to protect from atherosclerosis.
Many people are allergic to tree nuts. What can they do? Seeds can be an excellent replacement for tree nuts. Take, for example, flaxseed. They contain about 45% oil, 35% carbs, 20% protein, and provide omega-3 fat, an alpha-linolenic fatty acid. High in soluble fiber which slows food digestion, flaxseed is a low-glycemic food item, meaning it won’t spike your blood sugar. A randomized, 12-week study in people with prediabetes (those at risk of developing type 2 diabetes ) observed similar results in those who consumed 2 tablespoons of ground flax seeds daily. 12 Can flaxseeds help diabetic individuals? A 4-week study of 29 people with type 2 diabetes found that consuming 3/4 a tablespoon of flaxseed powder daily reduced fasting blood sugar by 19.7% and A1c by 15.6% compared with the control group. The flax group also experienced a favorable reduction in total cholesterol (14.3%), triglycerides (17.5%), and LDL cholesterol (21.8%). 13 Since raw flaxseed has a vitamin B-6 inhibitor, it is better to use it in cooking or baking. Flaxseeds have a blood-thinning effect. People with diabetes have an increased risk of forming undesirable clotting. However, if one is taking a blood-thinning medicine, they should eat other healthful fats.
Test tube, culture dish, and animal studies provide evidence that sesamin, (a major lignin isolated from sesame ) seeds and sesame oil, provide anti-oxidant, anti-inflammatory, anti-hypertensive, anti-atherogenic, anti-thrombotic, anti-diabetic, and anti-obesity effects. Sesamin can also impede the development of type-II diabetes by protecting pancreatic β-cells 14
Diabetes can potentially damage the liver by increasing free radical damage and inflammatory assaults. A 90-day controlled study of Type 2 diabetic individuals showed that white sesame seeds significantly reduced A1c levels and improved the antioxidant capacity of the liver. 15
The vascular endothelium composes the innermost layer of blood vessels and produces molecules and hormones that open up or constrict arteries. This layer is central to regulating vascular tone (the balance between blood vessel constriction and dilation) and regulates the passage of molecules and cells from the blood to the tissues. Vascular endothelium dysfunction is a major characteristic hallmark of cardiovascular diseases. Endothelial dysfunction occurs when the vascular endothelium produces more vasoconstrictors than vasodilators. In hypertension, the blood vessels lose their ability to dilate appropriately. One modest study investigated the effect of sesame oil on endothelial dysfunction and blood flow in men with high blood pressure.Compared to the controlled group, the participants who took sesame oil for two months had increased blood flow.16
Sunflower seeds have at least five known anti-diabetic compounds. They also contain 20% of proteins that provide sulfur and nitrogen. These sulfur-rich proteins help insulin production. Chlorogenic acid and caffeic acid in sunflower seeds can potentially reduce the severity of diabetes.17
Avocados are rich in potassium. One avocado provides 60% more potassium than a banana! Potassium helps to regulate blood pressure. It also regulates the electrolyte balance in the body which is essential for conducting electrical signals in the heart. Avocados are rich and abounding in many nutrients: β-carotene, tocopherol, retinol, ascorbic acid, thiamine, riboflavin, niacin, pyridoxine, and folic acid. 18
Avocado consumption improves cardiovascular health by reducing LDL cholesterol levels. The phytosterols in avocado inhibit cholesterol absorption and synthesis. Small-dense LDL (sdLDLs) cholesterol is the most dangerous because it penetrates the arteries easily. Once inside, the small-dense lipoproteins stay longer in the blood vessels. Individuals with diabetes have elevated sdLDLs. Avocado consumption helps to lower LDL.
Ninety percent of type 2 diabetic individuals are obese. One study showed the inclusion of avocado in a meal increased satisfaction by 23%, with a decrease in eating by 28% in obese adults. It improved their BMI (body mass index) and insulin levels.19
Green ripe olives also have phytochemicals that improve cardiovascular health. We will discuss olives in a future article.
Unsalted tree nuts, seeds, avocados, and olives are the very best fats to eat for cardiovascular health. Remember portion sizes. One serving of nuts and seeds would be 1/4 cup, or half an avocado, or 12 medium size olives. Oils should be used very sparingly and very rarely by individuals who have cardiovascular conditions or diabetes. Regular processing strips oils of most of its beneficial phytochemicals. When used, only cold-pressed flaxseed, olive, or almond oil should be used but never in frying. Essential fatty acid are fats you must obtain from your diet because your body does not make them. It is extremely difficult to obtain the daily requirements of these important fatty acids if you eat less than 15% of your total calories from fat.
- Guasch-Ferré, M. Frequency of nut consumption and mortality risk in the PREDIMED nutrition intervention trial. BMC Medicine, 2013; 11: 164 DOI: 10.1186/1741-7015-11-164↩
- Penn State. “Pistachios may lower vascular response to stress in type 2 diabetes.” ScienceDaily. ScienceDaily, 5 August 2014. www.sciencedaily.com/releases/2014/08/140805163347.htm↩
- Jenkins, D. J. Nuts as a Replacement for Carbohydrates in the Diabetic Diet. Diabetes Care, 2011; DOI: 10.2337/dc11-0338↩
- Cohen, AE, Almond ingestion at mealtime reduces postprandial glycemia and chronic ingestion reduces hemoglobin A(1c) in individuals with well-controlled type 2 diabetes mellitus. Metabolism. 2011 Sep; 60(9):1312-7↩
- Mori, AM, Acute and second-meal effects of almond form in impaired glucose tolerant adults: a randomized crossover trial. Nutr Metab (Lond). 2011 Jan 28; 8(1):6↩
- Jackson CL, Hu FB. Long-term associations of nut consumption with body weight and obesity. Am J Clin Nutr. 2014 Jul;100 Suppl 1:408S-11S↩
- Katz DL. Effects of walnuts on endothelial function in overweight adults with visceral obesity: a randomized, controlled, crossover trial. J Am Coll Nutr. 2012 Dec; 31(6):415-23↩
- Tulipani, S. Metabolomics Unveils Urinary Changes in Subjects with Metabolic Syndrome following 12-Week Nut Consumption. Journal of Proteome Research, 2011; 110929134856005 DOI: 10.1021/pr200514h↩
- American Physiological Society. “Pine Nut Oil Boosts Appetite Suppressors Up To 60 Percent For 4 Hours.” ScienceDaily. ScienceDaily, 4 April 2006. www.sciencedaily.com/releases/2006/04/060404085953.htm↩
- Brigham and Women’s Hospital. “Frequent nut consumption associated with less inflammation: Five or more servings of nuts per week or substituting nuts for animal proteins tied to a healthy profile of inflammatory biomarkers..” ScienceDaily. ScienceDaily, 29 July 2016↩
- Ros, ibid↩
- Hutchins AM. Daily flaxseed consumption improves glycemic control in obese men and women with prediabetes: a randomized study. Nutr Res. 2013 May;33(5):367-75. doi: 10.1016/j.nutres.2013.02.012.↩
- Mani UV, Mani I, Biswas M, Kumar SN. An open-label study on the effect of flax seed powder (Linum usitatissimum) supplementation in the management of diabetes mellitus. J Diet Suppl. 2011 Sep;8(3):257-65. doi: 10.3109/19390211.2011.593615.↩
- Dalibalta S, Majdalawieh AF, Manjikian H. Health benefits of sesamin on cardiovascular disease and its associated risk factors. Saudi Pharm J. 2020 Oct;28(10):1276-1289. doi: 10.1016/j.jsps.2020.08.018.↩
- Aslam F, et. White Sesame Seed Oil Mitigates Blood Glucose Level, Reduces Oxidative Stress, and Improves Biomarkers of Hepatic and Renal Function in Participants with Type 2 Diabetes Mellitus. J Am Coll Nutr. 2019 Mar-Apr;38(3):235-246. doi: 10.1080/07315724.2018.1500183.↩
- Karatzi K. Sesame oil consumption exerts a beneficial effect on endothelial function in hypertensive men. Eur J Prev Cardiol. 2013 Apr;20(2):202-8. doi: 10.1177/2047487312437625.↩
- Rehman A, Saeed A, Kanwal R, Ahmad S, Changazi SH. Therapeutic Effect of Sunflower Seeds and Flax Seeds on Diabetes. Cureus. 2021 Aug 17;13(8):e17256. doi: 10.7759/cureus.17256.↩
- Bhuyan DJ, et al. The Odyssey of Bioactive Compounds in Avocado (Persea americana) and Their Health Benefits. Antioxidants (Basel). 2019 Sep 24;8(10):426. doi: 10.3390/antiox8100426.↩
- A randomized 3×3 crossover study to evaluate the effect of Hass avocado intake on post-ingestive satiety, glucose and insulin levels, and subsequent energy intake in overweight adults. Nutr. J. 2013;12:155. doi: 10.1186/1475-2891-12-155.↩