What causes pimples?

A pimple is a small pustule or papule. Pimples develop when sebaceous glands, or oil glands, become clogged and infected, leading to swollen, red lesions filled with pus.

Also known as spots or zits, pimples are a part of acne. They are most likely to occur around puberty, but they can happen at any age.

During puberty, hormone production changes. This can cause the sebaceous glands, located at the base of hair follicles, to become overactive. As a result, pimples are most likely to occur during the teenage years and around menstruation, for women.

Pimples most often affect the face, back, chest, and shoulders. This is because there are many sebaceous glands in these areas of skin.

Acne vulgaris, the main cause of pimples, affects over 80 percent of teenagers. After the age of 25 years, it affects 3 percent of men and 12 percent of women.

Here are some key points about pimples. More detail is in the main article.

• • Pimples range in severity, from blackheads to cysts.
  • They happen when the sebaceous glands become more active, dead skin cells clog the pores, and sometimes an infection develops.
  • Pimples often occur in adolescence, but they can affect people at any age.
  • There is not enough evidence to confirm that any particular food causes acne, but following a healthful diet may reduce the risk.

Types

Blackheads, whiteheads, and cysts are all kinds of pimples, but what makes them break out?

There are several different types of pimples, and they have different signs and symptoms:

Whiteheads: Also known as a closed comedo, these are small pimples that remain under the skin. They appear as a small, flesh-colored papule.

Blackheads: Also known as an open comedo, these are clearly visible on the surface of the skin. They are black or dark brown, due to the oxidation of melanin, the skin’s pigment.

Some people mistakenly believe they are caused by dirt, because of their color, and scrub their faces vigorously. Scrubbing does not help. It may irritate the skin and cause other problems.

Papules: These are small, solid, rounded bumps that rise from the skin. They are often pink.

Pustules: These are pimples full of pus. They are clearly visible on the surface of the skin. The base is red and the pus is on the top.

Nodules: These have a similar structure to papules, but they are larger. They can be painful and are embedded deep in the skin.

Cysts: These are clearly visible on the surface of the skin. They are filled with pus and are usually painful. Cysts commonly cause scars.

Why do pimples happen?

Pimples happen when pores become clogged with sebum and dead skin. Sometimes this leads to infection and inflammation. Why they affect some people more than others is largely unknown.

The sebaceous glands and pimples

The sebaceous glands are tiny skin glands that secrete sebum, a waxy or oily substance that lubricates the skin and hair.

Sebaceous glands are found inside the pores of our skin, all over the body, except the palms of the hands and soles of the feet. There are more sebaceous glands on the face and scalp than elsewhere.

As the glands produce sebum inside the pores, new skin cells are constantly growing, and the outer layers of skin are being shed.

Sometimes, dead skin cells are not shed. They remain in the pores and get stuck together by the sticky sebum, causing a blockage in the pore.

Pore blockage is more likely to occur during puberty, as the sebaceous glands produce more sebum at this time.

Bacterial infection

Where sebum and dead skin cells accumulate and block a pore, this encourages the growth of undesirable bacteria, including Propionibacterium acnes (P. acnes), a slow-growing bacterium linked to acne.

Propionibacterium acnes exists harmlessly on our skin, but when the conditions are right, it can reproduce more rapidly and become a problem. The slow-growing bacterium feeds off the sebum and produces a substance that causes an immune response. This leads to skin inflammation and spots.

Although pimples are related to bacterial infection, they are not contagious. One person cannot catch pimples from another.

Risk factors

It is unclear exactly why some people are more prone to pimples than others. Hormone fluctuation and genetic factors may play a role, as acne often runs in families, but some other factors are possible.

Good and bad bacteria

Gentle washing may help prevent infection, but scrubbing can make pimples worse.

Just as in the gut, we have “good” bacteria that protect against disease and “bad” bacteria that cause disease, scientists have suggested that the same may be true for the skin.

Researchers at the Washington University School of Medicine identified two unique strains of P. acnes in the skin of 20 percent of people with pimples, while those with healthy skin tended not to harbor these strains. source

Another strain of P. acnes had the opposite effect. People with pimples tended not to have this strain, but those with healthy skin did have it.

This may indicate that particular types of bacteria determine the severity and frequency of pimples. The researchers suggest that these bacteria may also interact with different factors, such as hormone and sebum levels. They call for more research.

Yeast infections

Acne-type breakouts have also been linked to yeast infections.

Pityrosporum, also known as malassezia or folliculutis, happens when a pityrosporum yeast enters the hair follicles and multiplies, triggering an itchy eruption of tiny, itchy, rounded pimples, that resembles acne. It mainly occurs on the upper chest, shoulders, and upper back, but it can also affect the face.

Most people have this yeast on their skin, but if too much develops, it can cause a problem. It can happen to both men and women in young to middle-age.

Humid, sweaty environments, clothes made of synthetic fibers, and the use of oily skin products can all make this worse.

The condition is common in adolescents, probably because of increased sebaceous gland activity. It is not the same as acne, but it is often confused with it.

Antibiotics that are usually used for acne can make also make the condition worse, as they suppress the bacteria that would otherwise control the yeast. Antifungal treatment is needed in the case of malassezia.

Testosterone sensitivity

Researchers have found a link between acne pimples and higher levels of testosterone and other androgens, the “male” hormones that also exist in lower levels in females.

Higher testosterone levels appear to to trigger greater activity in the sebaceous glands, resulting in more clogged pores and higher chance of acne.

Dietary factors

The role of diet in acne is unclear, but, since a healthy, balanced, diet is known to promote good health, some dietary factors may affect the likelihood of getting acne or pimples.

Vitamins A, D, and E are all known to play a role in maintaining healthy skin, so it is possible that an adequate supply of these vitamins may help prevent acne.

Milk consumption has been associated with acne. If milk does play a role, this could be due to the hormones in milk. However, findings have been inconclusive.

It has often been said that sugar and chocolate trigger acne, but research findings have not supported this.

Studies have linked a low glycemic-index (GI) diet with lower levels of insulin in the blood, lower levels of androgen, and a reduced likelihood of acne.

However, the results are not conclusive. Moreover, advocating a low GI diet could discourage people from consuming enough whole grains and other healthful foods that could provide useful nutrients.

Although acne is related to sebum production, avoiding all fat in the diet is not advisable. Healthy polyunsaturated and monounsaturated fats are necessary for key bodily functions. A fat-free or very low-fat diet can cause the skin to dry out and prompt the body to increase sebum production.

A good intake of fats from nuts, seeds, and olive oil may help by keeping inflammation in check, supporting the body in maintaining healthy blood sugar levels, and maintaining good skin moisture levels so as to provide an effective barrier and immune response to prevent bacterial infection.

According to the American Academy of Dermatology (AAD), “There is not enough data to recommend dietary changes for acne patients.”

If dietary changes are to play a role in acne treatment, the AAD suggest that this should be as a “complement to proven acne treatments,” rather than as a sole treatment. They suggest that individuals monitor themselves to see what might trigger a breakout.

Tips include:

• keeping a food diary, and sharing it with a dermatologist
• waiting for 12 weeks after cutting out a particular food, as it may take time to see the impact
• continuing with regular acne treatment while making any dietary changes

Some medical conditions also increase the chance of pimples, for example, polycystic ovarian syndrome (PCOS).

Since acne appears to stem from a complex interaction of nutrients, hormones, and other factors, it is difficult to pinpoint exactly what causes pimples to worsen.

Insect Bites and How to Deal with Them

Which insects bite?

In the northern United States and Canada, biting insects include:

Insect bites can be painful and irritating, and some spread diseases.

• Bedbugs
• Fleas
• Flies, such as horseflies
• Gnats
• Midges
• Mosquitoes
• Spiders
• Ticks.

Individuals react in different ways. A bite that causes a small, itchy lump that disappears in a few days in one person can have a more serious effect on another.

If a bite becomes infected, there may be redness, warmth, and hardening of the surrounding skin, with pus draining from the wound.

Scratching the wound can lead to infection, and it can cause the skin to become thick and leathery skin. This is called “lichenification.”

People who work outdoors or regularly participate in outdoor activities are more susceptible to insect bites.

In colder climates, the risk of catching diseases from insect bites is small. However, nearer the equator insect bites can lead to malaria, sleeping sickness, dengue fever, or the Zika virus.

Reactions to insect bites

Insect bites normally cause a small itchy lump to develop on the skin. Sometimes the bite itself may be visible, as a tiny hole. The lump may be filled with fluid. The area around the lump is sometimes inflamed.

Insect bites normally disappear within a few days without medical attention.

Some people may have an allergic reaction to insect bites, but bites rarely cause a severe allergic reaction, unlike insect stings.

The following may indicate a severe allergic reaction:

Scratching a bite can give rise to infection.

• A rash, often blotchy, can spread to other parts of the body
• Breathing difficulties
• Chest pain
• Cramps
• Faintness or dizziness
• Nausea
• Rapid heartbeat
• Severe swelling, which may be far from the bite area, such as the tongue or lips
• Very severe itching
• Wheezing.

These symptoms require immediate medical attention.

Some people may have a stronger reaction the second time they are bitten by a particular type of insect. This is called sensitization. The individual becomes more sensitive to the insect’s saliva.

An infected insect bite can lead to:

• Pus inside or around the bite
• Swollen glands
• Fever
• A feeling of being unwell
• Flu-like symptoms.

The bite area may become redder with more pain and swelling.

An itchy papule or wheal may develop and persist for several days. Eventually, most people become immune and insensitive to the saliva, after being bitten a number of times.

Insect bite reactions do not normally last more than a few hours, but sometimes they can linger for months. In this case, the individual should consult a doctor.

Specific bites

Insect bites can have different effects.

Tick bites

The effects of a tick bite normally disappear within 3 weeks, but if mouth parts remain on the skin, signs and symptoms can persist. Ticks commonly occur in long grass and where deer live.

Tick bites are not generally painful, but a lump may develop. However, ticks can cause Lyme disease, Rocky Mountain Spotted Fever, Ehrlichiosis, and Babesiosis, among others. These common conditions can be serious.

Midges, mosquitoes, and gnats

Bites normally cause small, itchy lumps, or papules. Blisters or weals may develop in sensitive individuals.

Mosquito bites can transfer diseases, such as malaria, Zika, dengue fever, yellow fever, and encephalitis.

Fleas

A flea bite typically leads to a wheal that normally peaks in 5 to 30 minutes, and then becomes a hardened papular lesion within 12 to 24 hours. Sensitive people may find the site will itch for a week or more. Fleas can transmit diseases such as typhus and Yersinia pestis (Y. pestis), commonly known as plague.

Horseflies

Horseflies can deliver a painful bite. This may be accompanied by:

• Dizziness
• Eyes and lips may be itchy, with pink or red swellings
• Fatigue
• General weakness
• Hives (urticaria, a rash of wheals)
• Wheezing.

Horsefly bites may take a long time to heal, because the insect cuts into the skin when it bites.

Bedbugs

Initial bedbug bites do not generally cause a reaction, but sensitized individuals may develop weals or papules after a subsequent bite. Find out more about bedbugs.

Bed bugs constitute a major public health problem.

Getting rid of bed bugs includes throwing away the mattress and washing sheets and clothes in very hot water.

Spiders

All types of spiders bite, and some are quite dangerous to humans.

The bite of the brown recluse produces only a mild sting at the time of the bite, but it can be very damaging, causing tissue destruction and severe pain.

The brown recluse spider can inflict a damaging bite.

Redness develops in the bite area, and pain may become intense within about 8 hours. A fluid-filled blister forms at the puncture site. The blister then sloughs off, leaving a deep, enlarging ulcer. Sometimes, this ulceration goes away without any further problems, but sometimes this ulceration spreads or becomes superinfected by bacteria.

Symptoms include a mild fever, listlessness, nausea, and sometimes a rash. Death is rare but possible, especially in small children. You should seek medical attention if you believe that you have been bitten by a brown recluse and have a spreading ulceration or redness/infection of the area.

The black widow is the most venomous spider in the U.S., but its bite is rarely deadly. The bite feels a pinprick in the skin. There may be slight a swelling and faded red marks, but within a few hours, stiffness and extreme pain may develop.

There may also be:

• Chills
• Fever
• Nausea
• Extreme abdominal pain.

Anyone who believes they have been bitten by a black widow spider, and who is experiencing severe pain and stiffness near the area of the bite, should seek emergency care.

Depending on the severity of the reaction to the venom, doctors may decide to use antivenom to treat the bite.

What increases the risk of insect bites?

The likelihood of receiving an insect bite depends on the environment.

Common sources of fleabites include pets, crowded communities with low hygiene standards, and birds’ nests. Moving into a new home that has been empty for a while can activate dormant fleas.

Bedbugs favor old properties and upholstery. They commonly occur in low-income rental properties and hotels. They live in mattresses, clothing, and so on.

Some people are more prone to bites from ticks and mice because of their occupation.

Traveling and camping can increase the risk of insect bites.

Diagnosis and treatment of insect bites

Insect bites are normally easy to diagnose, but a person will only contact the doctor if there is a severe reaction.

If symptoms persist or are severe, it is a good idea to see a dermatologist.

A mild and limited reaction normally passes within a few days. A cold compress on the affected area, oral painkillers, a steroid cream, or anesthetic cream may soothe the discomfort. Antihistamine sometimes helps.

A more serious local reaction may require oral antihistamines or oral analgesic.

In more severe cases of swelling, the doctor may prescribe oral steroids.

Small, itchy lumps or lesions near bite can be treated with an oral corticosteroid, such as prednisolone, or an oral antihistamine.

Scratching the skin or bursting a blister can enable bacteria to enter and cause an infection.

If there are large skin reactions and more generalized symptoms, the doctor may refer the patient to a specialist for desensitization, or treatment for an allergic reaction.

If symptoms worsen or do not improve, medical attention should be sought.

If bites are from fleas, mites or bedbugs, the patient should try to find where the infestation is. If it comes from a pet, the pet will need treating, as well as its bedding, soft furnishings, and carpets throughout the house.

Bedbugs will mean calling pest control company to come and decontaminate the home. To prevent bedbugs, bedding should be washed often at a high temperature, and old pillows and mattresses replaced.

Tick bites

The tick must be removed immediately, to lower the risk of an infection, such as Lyme disease.

The best way is to hold the tick as close to the skin as possible, preferably with a pair of tweezers, and pull it straight up, making sure all its parts are removed.

Twisting or jerking it are not advised, as this can break it, leaving bits behind in the skin. Petroleum jelly, alcohol, or a lit match are not effective.

The hands and the bite area should be washed with soap and water after removing the tick, and an antiseptic applied.

Scratching increases the chance of swelling, and it raises the risk of infection. Most tick bites will heal within 2 to 3 weeks.

If a rash develops around the armpit, thighs or groin, or if there are flu-like symptoms, it is important to seek medical attention. The doctor will probably prescribe antibiotics to prevent Lyme disease.

Complications of insect bites

A secondary bacterial infection, such as cellulitis, lymphangitis, or impetigo, can result if the bite area is scratched and the skin is broken. This can be treated with antibiotics.

Some ticks carry diseases, such as Rocky Mountain spotted fever and Lyme disease.

Lyme disease is caused by Borrelia burgdorferi, a bacterium that some ticks carry. The patient develops a red rash that spreads outwards. Lyme disease can be treated with antibiotics.

Untreated Lyme disease may lead to meningitis, facial palsy, radiculopathy, and, rarely, encephalitis. Other risks include joint damage, leading to arthritis, and heart problems.

Different types of mosquito transmit different diseases, for example, West Nile virus and malaria.

Preventing insect bites

To prevent insect bites, especially in warm weather, the following steps may help:

• Using structural barriers, such as window screens or netting
• Avoiding wooded, brushy and grassy areas
• Avoiding heavily scented cosmetics and bright colored clothing
• Covering drinks and garbage cans
• Wearing long sleeves and long pants, tucked into shoes or socks, and a hat
• Checking containers for stagnant water, as this provide a breeding ground for mosquitoes.

Insect repellants

It may be necessary to use an insect repellent. The active ingredient should be approved by the Environmental Protection Agency (EPA). It can be sprayed onto clothes and skin, but not the face. It is important to follow the product’s instructions carefully.

Insect repellent is not suitable for infants. If a child is less than 10 years old, the repellent should contain no more than 10 percent DEET. Oil of eucalyptus can be effective, but it is not suitable for children under 3 years old.

Repellent should not be applied to children’s hands, around the eyes, or to areas where there are cuts and irritated skin.

When using an insect repellent and a sunscreen, the sunscreen should be applied first.

Clothes, shoes, and camping gear can be purchased or treated with permethrin. Tents should be pitched away from water or swamps.

Travelers should check whether the area they are going to has a risk of infection, and take the necessary precautions.

Local health departments and park authorities can provide information about tick-infested areas. If it is not possible to avoid a tick-infested area, it is best to walk in the center of paths, to avoid contact with vegetation.

Severe obesity may be caused by this genetic mutation

What causes obesity? This question continues to puzzle scientists and those living with the condition.

An increasing amount of studies are helping to remove the social stigma surrounding obesity, pointing to appetite-controlling hormones or even brain cells as potential causes.

Some are also pointing to genetic mutations as potential culprits for the condition. For example, Medical News Today have recently reported on a study in which mice gained weight without eating more as a result of having a certain gene variant. This made the researchers refer to the phenomenon as “fault-free obesity.”

Another previous study — led by Prof. Philippe Froguel, who is chair of genomic medicine at Imperial College London (ICL) in the United Kingdom — found that variants in three genes accounted for 30 percent of the severe obesity cases identified in a Pakistani population.

The same team of ICL researchers have now chosen to focus on a group of Pakistani children with extreme obesity from consanguineous families, or those that descend from the same ancestor, in an attempt to single out a specific gene mutation.

As the authors of the new study explain, so-called recessive mutations are responsible for the link between obesity and genes. Recessive inheritance occurs when both copies of the gene — that is, from both parents — have the mutation, and this is more likely to occur when a child’s parents are closely related.

So, Prof. Froguel and colleagues used genome sequencing in Pakistani children because people in this region are more likely to form consanguineous marriages, and the resulting children are more likely to have recessive mutations.

The new study — which was recently published in the journal Nature Genetics — suggests that mutations in a gene called adenylate cyclase 3 (ADCY3) lead to obesity.

ADCY3 gene mutation may cause obesity

According to the authors, mutations in this gene — which is normally responsible for encoding the protein of the same name — causes changes in functions such as appetite regulation and the olfactory sense.

As Prof. Froguel explains, “Early studies into ADCY3 tested mice that were bred to lack that gene, found that these animals were obese and also lacked the ability to smell, known as anosmia.”

As expected, they found the same ADCY3 mutation in children. Also, as Prof. Froguel explains, “When we tested our patients, we found that they also had anosmia, again showing a link to mutations in ADCY3.”

Additionally, using the GeneMatcher website, Prof. Froguel and colleagues found another patient — this time of European-American descent — who had inherited different ADCY3 mutations from both parents and who also had obesity.

Findings may lead to new obesity treatments

Together, the study authors conclude, “These findings highlight ADCY3 as an important mediator of energy homeostasis and an attractive pharmacological target in the treatment of obesity.”

Knowing precisely which genetic mutations lead to obesity will enable researchers to come up with drugs that target these mutations specifically, the authors explain.

Melanoma: Mutations that alter immune system to promote tumor growth identified

Scientists have discovered that the immune environment inside melanomas with mutations in ATR – a protein that normally identifies and repairs DNA damage caused by UV exposure – is altered in ways that promote tumor growth. They suggest that the finding could help to improve immunotherapies for melanoma and identify patients more likely to respond to them.

Researchers suggest that their study pinpoints a mechanism by which melanoma cells themselves can change the immune microenvironment inside tumors to ensure their continued growth.

Writing in the journal Cell Reports, University of California-Irvine (UCI) researchers describe how they found that tumors with ATR mutations recruit more pro-tumor macrophages and block the recruitment of anti-tumor T cells.

Senior author Anand K. Ganesan, associate professor of dermatology at UCI, explains that cancers arise “not only because they acquire mutations that promote their growth but also because they are able to prevent the immune system from recognizing and removing them.”

Melanoma is a cancer that usually begins in the melanocytes – skin cells that make melanin, the pigment that gives color to human skin, hair, and eyes.

Melanomas can arise anywhere on the skin, but they are more likely to begin on the legs in women and on the chest and back in men. Other common sites include the neck and face.

Cancers of the skin are the most common type of cancer by far, and while melanoma accounts for only 1 in every 100 cases, it causes the majority of deaths from skin cancer.

Rates of melanoma in the United States have risen over the past 30 years. The American Cancer Society estimates that in 2017, there will be around 87,110 new cases of melanoma and approximately 9,730 deaths from the disease.

Interaction between melanoma cells and immune cells

Immunotherapy is a relatively new field that is developing cancer treatments that work by promoting the body’s natural defenses to fight the disease.

Fast facts about melanoma

• The risk of developing melanoma increases with age
• However, it is one of the most common cancers in young people
• Exposure to UV light is a major risk factor for melanoma.

Learn more about melanoma

The more that researchers discover about the interplay between cancer and the immune system – particularly at the level of cells and molecules – the better are the chances of developing immunotherapies that target specific types of cancer.

In their study paper, Prof. Ganesan and colleagues mention that previous studies have revealed numerous ways in which interaction between melanoma cells and immune cells can influence tumor growth, spread, and resistance to treatment.

For example, cancer cells express PD-1 – a protein that reduces the ability of the immune system’s T cells to attack cancer cells.

Immunotherapy drugs that block PD-1 can activate the anti-cancer response and cause tumors to regress.

ATR mutations accelerate tumor growth

For their investigation, the team decided to focus on ATR – a protein that recognizes and repairs DNA damaged by exposure to UV light and which plays a role in cell reproduction.

They showed that introducing mutations that impair these functions in ATR into mice with melanomas accelerated tumor growth and the accumulation of mutations.

The authors also note that mouse melanomas with these ATR mutations “recruited proinflammatory macrophages while repelling T cells important for the anti-tumor response.”

Researchers suggest that their findings pinpoint a mechanism by which melanoma cells themselves can alter the immune microenvironment inside tumors to promote their continued growth.

The team also suggests that the mouse model they used in the study offers an ideal system for investigating how melanomas affect the immune response, as well as improving the design of immunotherapies.

Scientists discover enzyme that supports brain tumor growth

Researchers from the University of Texas MD Anderson Cancer Center in Houston have discovered that an enzyme helps brain tumors to grow. This finding offers the potential for new tumor treatment approaches.cv

A new study demonstrates how brain tumors can feed despite being in a microenvironment with restricted nutrients and oxygen.

All cancer tumors need to “feed” in order to grow and spread. Much like healthy cells, cancer cells are unable to live without the presence of oxygen and nutrients – but tumors are usually located in a nutrient-starved microenvironment.

New findings, published in Molecular Cell, illustrate how tumors manage to feed and grow despite their relentless surroundings.

An enzyme known as acetyl-CoA synthetase 2 (ACSS2) is at the center of providing tumors with a route to survive. ACSS2 enhances the tumor’s ability to use acetate, a cellular salt, as a carbon-based source of food, instead of glucose. While glucose is more desirable to aid tumor growth, its supply in cancer cells is often limited.

Acetate provides the cancer cells that are located at the core of the tumor with a lifeline to not only survive while struggling with nutrient deficiency, but also a method to grow.

Cutting off this important nutrient pathway in cancer cells could be essential to preventing tumor growth and promoting cancer cell death. However, the immune system is unable to stop the nutrient pathway in cancer cells, and current therapies are ineffective.

Furthermore, it is not clear how ACSS2 travels from a liquid cell component called cytosol into the nucleus in a process known as nuclear translocation. If the nuclear translocation of ACSS2 could be stopped, so too would the cancer cell’s ability to maintain itself.

“Overcoming metabolic stress is a critical step in solid tumor growth. Acetyl coenzyme A (CoA), generated via glucose and acetate uptake, is a key carbon source for important cellular processes such as histone acetylation and gene expression,” says Zhimin Lu, Ph.D., professor of neuro-oncology and lead researcher of the study.

“However, how acetyl CoA is produced under nutritional stress is unclear. Our study explains the underlying mechanics of how this occurs, with ACSS2 as a novel and important method for gene expression under these circumstances.”

ACSS2 allows production of cellular structures to aid tumor development

Lu and colleagues used a gene-editing tool called CRISPR to explore the role of ACSS2 in histone acetylation by generating nuclear acetyl CoA from acetate inside the nucleus of the cell.

Histones are vital for gene regulation. They are proteins that act as “spools” for DNA to wind around. Histone acetylation is a modification process that is a key part of gene expression. Histone modification using a metabolic enzyme was found to be significant for cells to remain stable and for the development of tumors.

The ACSS2 enzyme allows lysosomes, which are cellular structures that are known to contribute to tumor development, to be produced. Moreover, ACSS2 promotes autophagy – a “cannibalistic cell-feeding mechanism” – which, in turn, enables lysosomes to obtain, digest, and recycle key nutrients.

What is more, if nutrients outside the cell are in short supply, ACSS2 reprograms the cancer cell’s metabolism for cell survival and growth in two ways: by increasing autophagy, and by reusing products digested by lysosomes.

How to improve circulation

Circulation is the process by which the heart pumps a person’s blood around their body. Good circulation is vital to a person’s health. So, how can someone improve their circulation?

As the blood circulates, it delivers oxygen and nutrients to the body’s cells and takes away waste products.

This article discusses six ways to improve circulation that are supported by scientific evidence.

How to improve circulation

Avoiding a sedentary lifestyle may help to improve circulation. Jogging and avoiding sitting still for too long are both steps to take.

If a person wants to improve their circulation, there are some obvious places to start. These include:

• stopping smoking tobacco products
• reducing intake of saturated fats
• trying not to sit still for long periods

In addition, trying one or more of the following may help improve circulation:

1. Maintaining a healthy weight

Maintaining a healthy weight helps promote good circulation. If a person is overweight, it may negatively affect their circulation.

A 2009 study found that losing weight improved circulation for women who were overweight. The participants increased their levels of a protein called adiponectin that is associated with vascular function.

2. Jogging

Regular cardiovascular exercise, such as jogging, supports the health of the circulatory system and improves circulation.

A 2003 review noted that exercise improves the body’s ability to take in and use oxygen. It also improves the capacity of blood vessels to dilate, which helps them work more efficiently, allowing the muscles to receive oxygen more easily.

These benefits of exercise improve circulation and mean that daily activities may be less tiring.

3. Practicing yoga

Yoga is a low-impact exercise that is easy to modify for beginners. It involves bending, stretching, and twisting. These movements can help to compress and decompress a person’s veins, which may improve circulation.

A 2014 review of evidence published in the European Journal of Preventive Cardiology found yoga was beneficial for the cardiovascular system and a person’s metabolism.

A simple yoga position for beginners to try is the downward-facing dog. This helps improve circulation as it puts the hips and heart above the head, allowing gravity to increase blood flow towards the head.

To do the downward-facing dog, a person should:

• start on all fours, with shoulders above wrists, and hips above knees
• breathe in
• push hips backward and up into the air while exhaling
• straighten the arms and legs
• press firmly into the hands
• breathe deeply, lifting and pressing down each heel in turn to deepen the stretch
• let the neck relax
• stay in position for three deep breaths
• slowly lower hips back into starting position

4. Eating oily fish

The omega-3 fatty acids in oily fish promote cardiovascular health and improve circulation, according to this 2013 study.

Oily fish include:

• salmon
• mackerel
• sardines
• tuna

For those who are vegetarian or vegan, kale contains a small amount of omega-3 fatty acid.

Supplements containing omega-3 fatty acids are another option for people who do not eat fish.

5. Drinking tea

The antioxidants in tea promote cardiovascular health and may improve circulation. This is true for both black tea and green tea.

A 2001 study, published in the journal Circulation, found that black tea improves blood vessel health. Healthy blood vessels help improve circulation.

Another study found that green tea consumption is associated with a lower rate of coronary artery disease.

6. Keeping iron levels balanced

Iron is an essential mineral for the circulatory system. It is required to make hemoglobin, one of the major components of red blood cells, which is needed to carry oxygen.

Eating foods rich in iron, such as red meat or spinach, helps the body maintain this essential mineral. However, maintaining a healthful balance is necessary as well.

Too much iron may negatively affect cardiovascular health. A 2013 study found a link between having too much iron in the body and cardiovascular disease in people with high cholesterol and higher waist circumference measurements.

Causes and risk factors

Low blood pressure may affect circulation.

The health of a person’s circulatory system determines how well the blood circulates through their body. The factors that affect this include:

Blood pressure

Blood pressure is the pressure of the blood on the walls of the blood vessels as it circulates. Blood pressure is measured by “systolic” pressure over “diastolic” pressure.

Systolic pressure is the pressure on the blood vessel wall during the heartbeat when the lower chambers of the heart are pumping blood forward.

Diastolic pressure is the pressure on the blood vessel wall when the lower chambers of the heart are at rest and filling with blood.

According to the American Heart Association, a normal resting blood pressure in an adult is no more than 120 millimeters (mm) of mercury (Hg) systolic and no more than 80 mm for diastolic. This is abbreviated to 120/80 mmHg.

People with very low blood pressure may experience poor circulation and other related symptoms. However, having a lower blood pressure measurement is not usually a cause for concern in people with a healthy cardiovascular system.

Blood health

The blood carries oxygen and nutrients and removes waste and does these jobs best when it is healthy.

Healthy blood has the right levels of normal red blood cells, which carry oxygen, white blood cells, and platelets. These components are all made in the bone marrow.

Heart health

The heart is the muscle responsible for pumping a person’s blood around their body. The stronger and healthier a person’s heart is, the better their circulation.

Blood vessel health

Having healthy veins and arteries makes it easier for the blood to pass through them. If a person’s lipid or fat or their cholesterol levels are too high or low, the blood vessels can become injured and blocked.

Other causes

Poor circulation may be a symptom of other underlying health conditions. These include:

• obesity
• diabetes mellitus
• heart conditions
• conditions affecting the arteries or veins

Exercise and other measures to promote cardiovascular health may reduce poor circulation caused by these conditions.

Causes and remedies for cold feet

Having cold feet from time to time is normal, but people with poor circulation may feel cold more often. Learn about other causes and home remedies.

Signs and symptoms poor circulation

Numbness, tingling, and pain in the arms or legs may be symptoms of poor circulation.

If blood flow is reduced to a certain part of a person’s body, they may experience the signs and symptoms of poor circulation.

The following symptoms mainly occur in the arms or legs. They include:

• throbbing
• stinging
• numbness
• tingling
• cramps
• pain
• warmth or coolness