Low-density lipoprotein-cholesterol, more appropriately referred to as LDL-C or LDL cholesterol is the bad form of fat in our blood. Within the normal range, LDL-C does not harm the body. It is only when the levels cross their upper limit that LDL-C can pose a significant risk to your health. It can affect several systems of your body from head to toe.
Effects on Heart
Overly high LDL-C levels are a major cardiovascular risk. An excess of LDL-C can deposit within the walls of your coronary arteries (arteries supplying the heart) as fatty streaks, clogging them. The affected arteries harden over time. This hardening of arteries due to the fatty plaques is termed as atherosclerosis.
As these fatty deposits or plaques expand, they interrupt the blood flow to the heart muscle. The reduced supply of oxygen-rich blood to the heart triggers chest pain or angina. This occurs because the heart has to pump the blood harder through the narrowed arteries.
Consequently, a section of plaque can detach and form of a blood clot. With the passage of time, the clot can grow large enough to occlude the blood flow through a coronary artery. If the clot is not addressed at the appropriate time, an area of the heart muscle can eventually die, resulting in a heart attack.  The occlusion of blood supply can also trigger sudden cardiac death.
Besides, the hardened arteries become stiff so that the blood flowing through them exerts more pressure on their walls (aka raising the blood pressure), which defines hypertension.
LDL-C is an independent risk factor for cardiovascular disease.  In fact, measuring the amount of cholesterol carried by an LDL particle (LDL-C) is the best predictor of an impending coronary artery disease.
Effects of Raised LDL-C on Brain
The same clot can block an artery supplying your brain, leading to stroke. A person with stroke can become paralyzed or be unable to talk or walk depending on the area of the brain damaged.
The need to lower our LDL cholesterol becomes more obvious as the risk of memory loss and Alzheimer’s disease (AD) rises with the rising LDL-C levels. A putative link exists between high LDL levels and AD. High cholesterol or LDL levels in midlife can lead to cognitive decline in later life. This is probably because LDL-C favors the deposition of amyloid β-protein, the sticky substance that damages the brain in AD. Moreover, people who take statins (medicines to lower LDL levels) may already be protected against AD. This is in view of the statin’s potential to cross the blood-brain barrier and prevent AD. 
Keeping the LDL levels within the acceptable ranges can minimize the risk of cognitive impairment in later life.
Effects on the Peripheries
Peripheries of the body are the parts away from the center such as the arms, legs, hands, and feet. The fatty plaque can obstruct the arteries of the legs and arms, culminating in peripheral arterial disease (PAD).  This causes intermittent claudication or pain in the calf muscles when you walk or exercise, thereby limiting your physical activity.
Addressing your high LDL levels in PAD can slow the progression of the atherosclerotic plaque, impact your general cardiovascular health, reduce your chances of getting limb amputation, and, eventually, optimize your exercise tolerance. 
Effects on the Endocrine System
High LDL-C levels are also linked to type 2 diabetes. Whether high LDL levels cause diabetes or diabetes causes high LDL levels is unclear. That being said, many people with diabetes have deranged lipid profile, including low HDL (good cholesterol) and high LDL-C (small dense particles of LDL).
Effect on the Digestive System
In the gut, cholesterol plays a role in the production of bile. The enzymes in bile help break down the macronutrients in food so that they can be absorbed into your system easily. The body then gets rid of the excess cholesterol via bile. However, when the concentration of cholesterol in bile exceeds the bile’s removal capacity, the excess LDL cholesterol will precipitate into crystals and stones in your gallbladder. Too much of LDL cholesterol in the blood is a marker for gallstone disease that comes with its own risks. 
Thus, you can see that high LDL cholesterol levels can sabotage your health. A stitch in time saves nine so it is vital to fixing the raised LDL at the right time. In combination with the lifestyle modifications and the recommended medications, try supplementing probiotics to bring the LDL levels down. In particular, L. Reuteri NCIMB 30242 is proven to cut the bad cholesterol levels by around 12%. 
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