The 11 Body Systems - The Circulatory System
29 min read

11 Body Systems: what is the Circulatory System and how can you support it

11 Body Systems Author_Cliff-Harvey Education Product_Good-green-vitality

The 11 Body Systems are a collection of organ systems made up of parts that are able to work together to serve a common purpose – growth, reproduction and survival.

Each part of a system depends on the other parts to perform tasks that can’t be achieved by single parts acting alone and help to improve our chances of survival by maintaining a stable internal body environment.

This stable environment is known as homeostasis. Our series, 11 Body Systems goes into depth about each body system and how it relates to the rest of the body.

Why is the Circulatory System important?

Oxygen and nutrients are required to keep the cells of the body functioning.

The circulatory system delivers these to cells and takes waste away both directly, and via the sub-system of the lymphatic system.

The circulatory system also carries chemical messengers (hormones and neurotransmitters) that direct cells and ultimately, tissue and organs, to do what is required to keep the body healthy and in balance.

What is it made up of?

The circulatory or cardiovascular system is made up of the heart and blood vessels which deliver nutrients, oxygen, and messages to cells, including arteries 'arterioles' capillaries, and take away deoxygenated blood in venules and veins.

How can I support circulatory health?

Cardiovascular health is most affected by the body‘s ability to resist oxidative, glycation (sugar-related), and inflammatory damage.

So, the health of the circulatory system is closely aligned with the of the entire body and especially how well we metabolise, transport, store, and excrete nutrients.

The term ‘cardiometabolic‘ is often used to describe this integration of systemic ‘metabolic‘ health and the health of the cardiovascular system.

Therefore, a nutrient-dense diet that helps to support a healthy metabolism and optimal partitioning of nutrients, along with reducing the effects of sugar-related damage, excessive oxidation and inflammation are essential to cardiovascular health.

Cardiovascular supporting ingredients in Good Green Vitality

Vitamin B1 - Thiamin

Thiamin deficiency is prevalent in heart failure patients and supplementation with this vitamin improves cardiac function, weight maintenance, and signs and symptoms of heart failure in patients. (1-3)

Thiamin deficiency could be part of the complex aetiology (causation) of heart disease and supplementation might reduce the risk of future cardiovascular events. (4)

Vitamin B2 - Riboflavin

Riboflavin is a relatively under-recognised anti-oxidant that can help reduce oxidative stress to the body. (5)

Cardiovascular disease patients with the MTHFR 677TT genotype and high blood pressure might experience significant reductions with riboflavin supplementation. (6)

Vitamin B3 - Niacin

Research suggests that niacin supplementation reduces cardiovascular disease events (7, 8) via its HDL-elevating, antioxidant and anti-inflammatory properties. (9)

Niacin has been shown to significantly improve lipid abnormalities in people with type 2 diabetes mellitus but requires monitoring of glucose levels if used for long term treatment. (10)

Vitamin B6 - Pyridoxines

There is a dose-dependent relationship between increased B6 intake and reduced cardiovascular risk. (11)

Many people (~20% of the population) do not habitually consume enough B6 in their diets, (12) and due to the critical role of this vitamin, in concert with the other b-vitamins, supplementation is recommended.

Vitamin B9 - Folate

Folate supplementation helps to reduce homocysteine (a cardiovascular risk marker) and inflammation and might help improve glucose control (which in turn helps to reduce sugar-related damage to the tissues of the body). (13-15)

Vitamin C

Increased vitamin C intake, vitamin C supplementation, and higher concentrations of vitamin C are associated with lower blood pressure (16) and beneficial effects on endothelial function (the cells that line the interior of blood vessels), particularly in those with cardio-metabolic disorders. (17)

Vitamin E

Pooled data from randomised controlled trials show a significant, positive effect of vitamin E supplementation on endothelial function (the thin membrane that lines the inside of blood vessels, which when damaged is a contributor to heart disease).

This effect is greatest for those with lower levels of vitamin E. (18) Supplementation with vitamin E also significantly reduces systolic blood pressure. (19)

Vitamin K

Research suggests that vitamin K supplementation significantly reduces vascular calcification, which is a marker for poor vascular health and is associated with cardiovascular events like heart attacks. (20)

In addition, there is evidence to show that vitamin K may help manage insulin sensitivity and glucose tolerance, (21) and therefore might help to reduce sugar-related damage to the vascular system.


The modern diet is assumed to provide enough copper but research has demonstrated that there might be a marginal (sub-clinical) deficiency in 38% of hyperlipidaemic patients (people with high blood triglyceride and cholesterol levels).

Supplementation with copper at ~ 5 mg per day improved cholesterol, LDL, HDL, and especially triglycerides. (22, 23)

Copper is also involved in antioxidant enzyme activities and supplementation in those with lower copper status improves levels of the important internal antioxidants; superoxide dismutase (SOD) and diamine oxidase (DAO). (24)


Magnesium status is important for preserving cardiac (heart) rhythm and supplements appear to reduce arrhythmia, (25) along with aiding endothelial function. (26)

Magnesium is involved in blood glucose regulation and people with metabolic syndrome and diabetes might achieve positive changes in blood glucose, insulin levels, and HDL and LDL cholesterol, and triglycerides from magnesium supplementation. (27-30)


High blood pressure is a risk factor for heart attack and stroke and research suggests that oral potassium supplementation can significantly and safely lower both systolic and diastolic blood pressure, with a greater magnitude in this blood pressure-lowering effect seen in those patients with hypertension, (31-33) those who consume high amounts of sodium, those not on hypertensive drug treatment, and those in the lowest category of potassium intake. (34)


Zinc status is often low in those with metabolic syndrome and zinc has been shown to reduce fasting and post-meal glucose, fasting insulin, HbA1c, and c-reactive protein, (35) and improves insulin resistance in both men and women. (36)

Zinc supplementation also significantly reduce triglycerides, cholesterol and LDL cholesterol. (37)


Flaxseed supplementation is considered to be beneficial for the cardiovascular system.

Systematic reviews and meta-analyses have shown significant reductions in blood pressure. (38, 39)

Other research suggests that flaxseed supplementation might help people to reduce weight and improve body composition (lean vs fat mass). (40)

Flaxseeds also help to regulate blood-sugar balance with reductions in blood glucose, insulin and insulin resistance models in those consuming supplemental flaxseed. (41)


Foods high in bioflavonoids like citrus, tea, coffee, red wine, pomegranate, and chocolate, have been considered to be beneficial to health overall and these foods have also been shown to reduce inflammation and oxidation. (42)

Reviews of observational studies suggest that increased bioflavonoid intake reduces the risk of cardiovascular disease, cardiovascular disease mortality, and all-cause mortality. (43-45)


Grapeseed extracts contain antioxidants that increase the total antioxidant activity of the body, (46) with a range of purported health benefits.

In a study of 150 and 300 mg of Grapeseed extract vs placebo, over 4 weeks, there was a significant reduction in blood pressure. (47)

A meta-analysis of studies up to 2011 confirmed this, with consistent, significant reductions in systolic blood pressure and heart rate. (48)

Grapeseed also improves blood flow and reduces oxidative damage to the cardiovascular system, (49) increases glutathione (a key antioxidant) concentration and reduce c-reactive protein (a marker of total body inflammation) in type 2 diabetics. (50)

Green Tea

Green tea catechins can help to reduce body-fat levels, and it has been hypothesised that this is due to synergistic effects including those of caffeine and green tea catechins on fat oxidation, (51-53) and there are also positive effects on blood glucose and insulin. (54)

Green tea catechins also result in significant reductions in blood pressure, total cholesterol and LDL-cholesterol. (55-58)

The antioxidant, chelating, and anti-inflammatory effects of green tea might also be able to help protect against the effects of environmental and lifestyle toxins. (59)


There are many purported benefits to overall health from the traditional use of Cocoa and Cocoa-containing foods and drinks for cardiovascular, neurological, oral, endocrine, immune, respiratory and reproductive systems, and these are beginning to be shown in modern, scientific studies. (60, 61)

Reviews of the research have shown that Cocoa and its plant phenols can improve insulin function and sensitivity, blood pressure, and improve flow-mediated dilation, (62, 63) important for proper blood flow and overall health of the cardiovascular system.

The benefits to blood pressure are greater than even drastic reductions in sodium. (64)

Cocoa flavanols can also improve HDL (‘good‘) cholesterol, and reduce triglycerides (fats in the blood) and insulin. (65)

Additionally, improvements in inflammation have been seen in those with diabetes and metabolic syndrome. (66)

Cocoa flavanols could benefit performance by improving mitochondrial efficiency, improving vascular function and reducing exercise-induced oxidative stress. (67)


the compound effects of antioxidant, anti-inflammatory, hypoglycaemic, hypolipidaemic, hypotensive, anti-atherosclerotic, anti-thrombotic, hepatoprotective, and hypocholesterolaemic actions of rosemary compounds have led to the suggestion that rosemary and rosemary extracts could be useful for cardiometabolic health. (68, 69)


Along with its other purported effects, it is likely that turmeric aids blood-glucose control, reduces cholesterol and blood lipids, and improves immune function, all of which help to improve cardiovascular health. (70)


Human evidence shows that resveratrol supplementation can reduce triglyceride levels (one of the key markers for future cardiovascular risk). (71)

A summary of randomised controlled trials found a significant reduction of body weight, BMI, and waist circumference, also markers of future health risk, from resveratrol supplementation. (72)

Resveratrol, in addition to its antioxidant roles, increase nitric oxide and this is thought to be the mechanism by which it can reduce hypertension (high blood pressure), (73) an effect mostly seen with doses of > 300 mg per day and in those with diabetes. (74)

In addition, resveratrol has been purported to be anti-inflammatory. In a review of 15 trials (n = 658), it was found to reduce C-reactive protein overall and also reduced tumour necrosis factor-α in young adults and those with obesity. (75)


Beta-glucans have demonstrated the ability to reduce blood glucose from either high doses (~ 6 g per day) or longer-term use of lower doses. (76) They can also reduce both total and LDL cholesterol, improving blood lipid profiles. (77, 78)

Co-enzyme Q10

CoQ10 has a relatively long history of use both for prevention of cardiovascular disease and as part of the supplemental regimen of those with heart disease, especially with statin use, which can reduce both production and availability of CoQ10 in the body. (79, 80) Meaningful reductions in blood pressure (up to 16 mm Hg reduction in systolic blood pressure) and improved mortality outcomes, and fewer cardiac events and complication for those with heart disease have been observed, (81-83) along with functional outcomes such as improved cardiac output and stroke volume. (82)

CoQ10 has also resulted in meaningful reductions (~ 0.3 mmol/L) of triglycerides, a key marker for cardiovascular and cardiometabolic risk. (84) For those with existing coronary artery disease, CoQ10 can improve HDL and total cholesterol levels. (85) The most recent reviews of the evidence conclude that CoQ10 is a useful tool for managing heart disease. (86)
In those with type 2 diabetes, CoQ10 might help to control blood glucose and improve triglyceride and HDL cholesterol concentration in the blood. (87)

Aloe Vera

Studies on oral use of Aloe vera extracts have shown reduced blood glucose, (88) cholesterol, triglycerides, LDL cholesterol, blood pressure, and improved HDL cholesterol. (89, 90)

Globe Artichoke

Globe artichoke appears to exhibit strong antioxidant activity, with increased superoxide dismutase, catalase, glutathione, and glutathione peroxidase levels. (91) At least one randomised controlled trial has demonstrated significant, modest reduction (~ -0.3 mmol/L) in total cholesterol resulting from globe artichoke supplementation. (92) An extract of globe artichoke has also resulted in improved blood glucose and insulin homeostasis in another randomised, double-blinded trial. (93)

Apple pectin

Apple pectin supplementation can reduce total cholesterol, LDL-cholesterol, triglycerides, and might have anti-obesity effects. (94, 95) Changes in the guts of laboratory animals from apple pectin supplementation have also been shown to increase the bioavailability of quercetin, an antioxidant bioflavonoid, (96, 97) with the suggestion that apple pectin may help improve overall nutriment and


Psyllium specifically is known to have cholesterol-lowering properties. (98) Reviews of the many studies that have been conducted on psyllium specifically show that it can help to reduce total and LDL cholesterol, apolipoprotein B, along with improve blood-sugar responses, and increases satiety. (99-101)

Milk Thistle

Milk thistle contains several flavonoids with antioxidant and anti-inflammatory properties. (102) It has also been found to have lipid-lowering, anti-diabetic, liver protective and blood-pressure-lowering properties and it is hypothesised that it may improve cardiometabolic health. (103)


Bromelain is now being studied for a range of health effects. It is considered to inhibit platelet aggregation, be anti-inflammatory and anti-tumour, and improve immunity and digestive function. It may also enhance wound-healing and provide
cardiovascular benefits. (104, 105)


Reviews of the scientific literature show a range of benefits from probiotic supplementation for weight- and fat-loss and reduced markers of diabetes and metabolic syndrome (106-110), reducing oxidation, (111, 112) inflammation and inflammation-related pain (113, 114), and improved cardiovascular markers (cholesterol and lipid profiles). (115)


Spirulina is thought to provide benefits for reducing oxidation (116) and improved cardiovascular and diabetic markers, (117) along with reduced inflammation. (118, 119) Reviews of the scientific literature show that spirulina might offer interesting, specific benefits to those with cardiovascular risk factors. It has been demonstrated to reduce total cholesterol and LDL-cholesterol and triglycerides, while increasing (‘good‘) HDL-cholesterol. (120)


Hawthorn has been mostly studied for its benefits in cardiovascular disease. A 2010 review of these studies concluded, current research to date suggests that hawthorn may potentially represent a safe, effective, nontoxic agent in the treatment of cardiovascular disease and ischemic heart disease. (121)

Read more about the 11 Body Systems with these two blogs:

What is the immune system and how can I support it...

How the digestive system works...


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