Relationship between Cholesterol and Diet

 Relationship between Cholesterol and Diet

Author Name: Afroz Gul (Home Economics Food & Nutrition)

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Abstract

The purpose of this research paper is to dispel the myths regarding cholesterol and dietary patterns. It also sheds light on the association between cholesterol and food items. Many studies have reported cholesterol-lowering properties of soluble dietary fibre. The in-depth analysis taken from different studies regarding cholesterol-lowering properties of different food items will help in providing baseline information for nutritional education and awareness. Besides, the risk of high cholesterol levels has been so long associated with the intake of eggs and red meat. Recent studies regarding egg consumption and cholesterol will highlight the newfound facts. Also, there is a lack of research on poultry's association with raising cholesterol levels.

1. Introduction

 Cholesterol- a type of lipid and a waxy substance- is essential for the body in the right amounts to produce estrogen, testosterone, vitamin D, and other significant compounds.  However, an increase in blood cholesterol levels poses many health risks (Blood Cholesterol | NHLBI, NIH). The dietary consumption of trans and saturated fats, as well as simple carbohydrates, raises its levels. Besides, cholesterol is found naturally in some food items. Nevertheless, dietary cholesterol does not increase as much blood cholesterol levels as fats and carbohydrates do (Cholesterol).

Also, cholesterol passes into the bloodstream in the guise of lipoproteins. The low-density lipoproteins (LDL) form plaque, narrowing down the walls of the arteries, leading to cardiac attack or a stroke. In contrast to LDL cholesterol, high-density lipoprotein (HDL) removes, reduces, and recycles LDL and removes the plaque from the walls. Besides, very low-density lipids- the third type of lipoproteins- are mostly triglycerides, required in the right amounts as higher amounts of them have harmful impacts on the body (Cholesterol).  It is worth pointing out that good and bad cholesterol can be increased and decreased, respectively, with the help of diet and lifestyle changes.

1.1 Statement of the Problem

This research paper will assess the relationship between cholesterol and diet.

 

1.2 Significance of the Study

The study will provide guidelines and information on the existing researches on cholesterol and diet. This information can be used for developing nutritional education awareness programs for the general masses.

1.3 Objectives

●       To find out the relationship between cholesterol and diet.

●       To find out about cholesterol-lowering properties of soluble dietary fibre.

●       To find out which foods have cholesterol-lowering properties.

●       To find out the effect of egg consumption on cholesterol levels.

●       To find out the impact of meat consumption on cholesterol levels.

1.4 Research Questions

●       What is the relationship between cholesterol and diet?

●       What is the relationship between soluble dietary fibre and cholesterol?

●       Which of the foods have cholesterol-lowering properties?

●       How does egg consumption affect cholesterol levels?

●       What is the effect of meat consumption on cholesterol levels?

2. The Review of Literature

2.1 Soluble Dietary Fiber and Cholesterol

 Soluble fiber decreases low-density lipoproteins (LDL) and total cholesterol by 5-10%. (Surampudi, Enkhmaa, Anuurad, & Berglund, 2016). Additionally, dietary fiber reduces LDL cholesterol levels by speeding up bile acid excretion (Bartley et al., 2010). The soluble dietary fibers include ß-glucan, psyllium, pectin, guar gum, arabinoxylans, and inulins (Surampudi, Enkhmaa, Anuurad & Berglund, 2016).

A.     ß-glucan and Mucilages and their Relationship with Cholesterol

Oats and barley have ß-glucan, and psyllium seeds have mucilages, which reduce cholesterol levels (Surampudi, Enkhmaa, Anuurad & Berglund, 2016). Furthermore, a study indicated that consumption of 3g per day of oat ß-glucan proved to have a higher efficacy rate in lowering LDL cholesterol levels in type 2 diabetic patients and in individuals having higher LDL levels. Barley ß-glucan also showed similar cholesterol-lowering properties (Whitehead, Beck, Tosh & Wolever, 2014). Solà et al., 2010 concluded that individuals having higher cholesterol levels had their LDL and triglycerides levels reduced when they were given a low-saturated-fat diet and psyllium husk, which is also commonly known as ispaghol.

B.     Pectin and their Relationship with Cholesterol

 Moreover, pectin- another soluble dietary fiber- is present in apples, citrus fruits, sugar beets, and carrots, which reduce serum cholesterol levels (Surampudi, Enkhmaa, Anuurad & Berglund, 2016). Consuming pectin 6 g per day prevents cholesterol levels from rising (NDA, 2010). Also, a study assessed the effects of citrus pectin and apple pectin in both genders having high cholesterol levels. 15 g per day of citrus and apple pectin helped to reduce bad cholesterol by 7-10% (Brouns et al., 2011).

C.    Arabinoxylans, Guar gum, and Inulin and their Relationship with Cholesterol

Additionally, wheat, rye, rice, sorghum, oats, corn, and barley have arabinoxylans, which, too, contain lipid-lowering effects (Surampudi, Enkhmaa, Anuurad & Berglund, 2016). Arabinoxylans- a soluble dietary fiber- hinders the absorption of fatty acids, which, in turn, helps lower cholesterol levels (Hartvigsen et al., 2014).  Total and bad cholesterol is also lowered by guar gum (Spiller, Farquhar, Gates & Nichols, 1991). Besides, a report analyzed that 10 g per day inulin helps lower triglyceride levels (Tovar et al., 2012).

2.2 Foods that Lower Cholesterol Levels

A.    Whole-grains

A study reported that oats or oat bran reduced total cholesterol by 2-19% and LDL levels by 4-23% in individuals with high cholesterol levels (Thies, Masson, Boffetta & Kris-Etherton, 2014). Hollaender et al., 2015 also concluded that whole grains help lower total cholesterol levels, as well as LDL levels and triglycerides. 

B.     Legumes

Anderson & Major, 2002 and Duranti, 2006 analyzed that legumes help lower the total cholesterol levels and LDL levels. In addition to this, Ha et al., 2014 investigated that 130 g per day of beans consumption lowers LDL cholesterol levels.

C.     Flax Seeds

Kristensen et al., 2012 evaluated that drinks made with flax seeds reduced total cholesterol by 12% and LDL levels by 15%. Furthermore, Katare & Saxena, 2014 assessed the efficacy of flax seeds in patients with dyslipidemia. For three months, these patients consumed roasted flaxseeds. It ultimately reduced total cholesterol, LDL cholesterol, triglycerides, and VLDL cholesterol levels. It also increased HDL cholesterol levels.

2.3 Eggs, Cholesterol, and Cardiovascular Disease

 It is a fact that high LDL cholesterol is linked with cardiovascular diseases while HDL cholesterol is good for heart patients. However, egg consumption does not raise cholesterol levels in heart patients. In past studies, egg consumption was associated with cardiovascular risks, as egg yolk is one of the richest sources of cholesterol.  But large-scale studies indicate that association between egg and cardiovascular diseases is negligible (Blesso & Fernandez, 2018). Although saturated fats increase LDL-cholesterol levels, eggs have only 2.5% of it (O'Neil, Keast, Fulgoni & Nicklas, 2012).

Another report analyzed that eggs do not have a link with cardiovascular risks. Contrarily, people with diabetes should limit eggs in their diet, as egg consumption was linked with cardiovascular risk in diabetic patients (Rong et al., 2013). But this may be associated with the phosphatidylcholine content of eggs instead of the cholesterol content (Zheng et al., 2016). It is because cholesterol is poorly absorbed in diabetic and obese patients (Pihlajamäki, Gylling, Miettinen & Laakso, 2004).

2.4 White Meat, Red Meat, and Cholesterol

Contrary to the popular belief, it has been reported that both poultry and red meat increases LDL cholesterol levels. Red meat has high saturated fatty acids, which raises LDL concentrations, but there is a lack of study regarding the association of LDL levels with poultry. It is widely believed that poultry should be preferred over beef by cardiovascular patients (Bergeron, Chiu, Williams, M King & Krauss, 2019).

3. Conclusion

 Although it is essential to limit saturated fat and cholesterol in your diet, there are certain beliefs widely spread around the globe regarding dietary patterns associated with cholesterol. This research paper has shed light on the basics of cholesterol-lowering dietary patterns. It has also highlighted that the link between egg and cardiovascular diseases is tenuous. Additionally, the cholesterol-lowering properties of ß-glucan, psyllium, pectin, guar gum, arabinoxylans, inulins, legumes, whole grains, and flax seeds have been discussed. Moreover, it has been found that it is not wise to choose red meat over white meat to reduce heart risks. Besides, it has provided accurate guidance in the light of recent studies, so people can make smart purchasing and cooking choices.

4. References

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