Cold sores are a common and often frustrating skin issue. While they may look like harmless blisters, cold sores are actually caused by the herpes simplex virus (HSV).

What Causes Cold Sores?

Cold sores are caused by the herpes simplex virus (HSV), which comes in two types: HSV-1 and HSV-2.

HSV-1 is the primary cause of cold sores, usually appearing around the mouth.

HSV-2 generally causes genital herpes but can also lead to cold sores.

While the appearance of cold sores caused by both HSV-1 and HSV-2 can look similar, their locations tend to differ. However, it is possible for HSV-1 to cause sores on the genitals and for HSV-2 to appear on the mouth.

How Do Cold Sores Spread?

Cold sores are highly contagious and can spread easily. The virus can be passed on through:

• Kissing or skin contact
• Sharing food, drinks, or cosmetics (such as lip balm)
• Oral sex, which can spread both cold sores and genital herpes

Even when a cold sore isn’t visible, the virus can still be spread through close contact. This makes prevention and management key to reducing outbreaks and the risk of infecting others.

Once someone contracts HSV, it stays in the body for life. While the virus remains dormant most of the time, it can reactivate and cause new sores, especially during periods of:

• Stress
• Illness
• A weakened immune system

Unfortunately, there’s no cure for the herpes virus, but the symptoms can be managed.

Symptoms of Cold Sores

Cold sores don’t just appear out of nowhere. Before the sore is visible, you may notice a tingling or burning sensation around the lips or face, which can occur several days before the sore forms. This is the best time to begin treatment to shorten the outbreak.

When a cold sore does appear, it often looks like a red, raised blister filled with fluid. The blister can be painful to touch, and there may be more than one. Cold sores usually last around two weeks and are contagious until they crust over and heal.

The Five Stages of a Cold Sore

Cold sores go through distinct stages as they develop and heal:

• Tingling and itching: You may feel these symptoms about 24 hours before the blister appears.
• Blisters: Small, fluid-filled blisters form, typically around the mouth.
• Bursting: The blisters burst and form painful sores.
• Scabbing: The sores dry out, scab over, and may itch or crack.
• Healing: The scab falls off, and the cold sore heals.

Risk Factors for Cold Sores

Certain factors can trigger the reactivation of HSV, leading to cold sores. These include:

• Infection, fever, or cold
• Sun exposure
• Stress
• Menstruation
• Dental work or injury
• Weakened immune system due to conditions like HIV/AIDS, eczema, or chemotherapy

Managing and Treating Cold Sores

There’s no cure for cold sores, but several treatments can ease the symptoms and help manage outbreaks.

Topical Ointments and Creams

Over-the-counter antiviral creams like docosanol (Abreva) or prescription ointments like penciclovir (Denavir) can help reduce the duration of an outbreak, especially if applied at the first sign of a cold sore.

Oral Medications

Prescription antiviral medications like acyclovir, valacyclovir, and famciclovir can also help, particularly for people who have frequent or severe outbreaks. Your doctor may recommend taking these medications regularly to prevent future outbreaks.

Home Remedies

There are also some home remedies that may provide relief, such as:

• Applying ice or a cold washcloth to the sore
• Using aloe vera gel or lemon balm lip balms
• Applying petroleum jelly to ease discomfort

Canker Sores vs. Cold Sores: What's the Difference?

While cold sores and canker sores may seem similar, they are quite different:

Cold sores are caused by the herpes virus, appear around the mouth, and are contagious.

Canker sores are not contagious and appear as ulcers inside the mouth or throat.

Preventing the Spread of Cold Sores

To avoid spreading cold sores:

• Wash your hands frequently
• Avoid close contact with others during an outbreak
• Don’t share food, drinks, or personal items like lip balm

Cold sores can be a persistent issue, but with proper care and management, you can reduce the frequency of outbreaks and prevent spreading the virus to others.

A new oral GLP-1 medication has delivered encouraging results in a Phase 2b clinical trial for people living with type 2 diabetes.

According to AstraZeneca, its experimental tablet, elecoglipron, significantly lowered blood sugar levels and helped participants lose an average of 10.5% of their body weight after 26 weeks of treatment.

The findings were presented at the 2026 American Diabetes Association Scientific Sessions in New Orleans and published in The Lancet on June 8.

Elecoglipron joins a growing wave of GLP-1 therapies being developed as pills, offering an alternative to injectable drugs such as Ozempic, Wegovy, Zepbound, and Mounjaro.

The first oral GLP-1 treatment, Rybelsus from Novo Nordisk, received FDA approval in 2019 for adults with type 2 diabetes. Since then, oral options have continued to expand. In December 2025, the FDA approved a tablet version of Wegovy for weight management, while Eli Lilly’s oral obesity treatment, Foundayo, gained approval in April.

Independent experts say AstraZeneca’s results highlight the growing potential of non-injectable GLP-1 therapies for both diabetes and obesity treatment.

“It’s encouraging to see another oral medication demonstrating the benefits of GLP-1 therapy without requiring injections,” said Dr. Pouya Shafipour, a family and obesity medicine specialist at Providence Saint John’s Health Center in California.

Dr. Marilyn Tan, an endocrinologist and professor of medicine at Stanford University, noted that the rapidly expanding GLP-1 market could soon welcome another oral treatment option if elecoglipron succeeds in Phase 3 trials and ultimately secures FDA approval.

How Does GLP-1 Drug Work?

GLP-1 is a natural hormone produced in the intestines that regulates blood sugar, appetite, and digestion. Now, every time you eat, your body produces various hormones, including GLP-1. These are called post-nutrition hormones, and they help you absorb the energy you just consumed.

GLP-1 travels to your pancreas, prompting it to produce insulin. It also travels to the hypothalamus in your brain, which gives you the feeling of being full or satiated. GLP-1 pills imitate that hormone, thereby silencing the food chatter in the brain. Interestingly, for some people, this food chatter is really quiet, and for others it is an outburst. So with GLP-1, silencing this self-talk in the brain, people tend to lose their appetite and eventually weight.

However, it is important to note that losing weight includes not just fat but muscle as well. Losing too much muscle can lead to reduced strength and a shorter life span. Notably, records show that most people who start taking them stop them at 12 weeks; therefore, it is important for some but not for others.

What Are The Side Effects?

The side effects of these pills include:

• Nausea is a frequent side effect, especially when starting or increasing the dose, and vomiting may occur along with nausea.
• Diarrhoea and abdominal discomfort also show up.
• It can reduce appetite but may also lead to unintended weight loss or reduced food intake, causing discomfort for some people.
• There are certain less common, but serious side effects, like Pancreatitis, or inflammation of the pancreas.
• This drug may also cause severe kidney issues, particularly if dehydration occurs from side effects like vomiting or diarrhoea.

The most frustrating skincare experience is breaking out a week after using a new product. Niacinamide serum is the most common one that people blame when it happens. But the real question is: does Niacinamide cause purging? The answer is no, but understanding what happens in your skin when you introduce it can help you.

A well-formulated Niacinamide Serum at the right concentration is very gentle on the skin.

And pairing it with a Niacinamide Moisturizer helps your skin adjust if you are using it for the first time.

What Is Skin Purging and How Is It Different from Breakouts

Skin purging is the result of an active ingredient accelerating your skin's natural cell turnover cycle. Your skin renews itself every 28 days. Retinol, AHAs, and BHAs speed up this process, which pushes microcomedones, trapped sebum, and dead cell buildup up to the surface faster.

Your skin may appear like it is experiencing a sudden flare-up of pimples, but it is your skin clearing all the buildup in one go. True purging:

• Happens only with ingredients that increase cell turnover
• Appears in the same areas you normally break out
• Resolves within four to six weeks
• Involves small whiteheads and blackheads rather than deep cysts

A regular breakout appears in new areas with any product and does not follow the same predictable timeline. Understanding this difference is important before you blame any ingredient.

Does Niacinamide Cause Purging?

Dermatologists say no, and the reason comes down to how niacinamide works at the biological level. Purging occurs only when an ingredient accelerates cellular turnover, forcing the skin to shed faster to clear hidden congestion.

Niacinamide is a form of Vitamin B3, and its action is fundamentally different. It works in the following manner:

• Regulates sebum production through the sebaceous glands
• Strengthens the skin barrier by supporting ceramide production
• Niacinamide reduces redness and inflammation caused by acne
• Stops the transfer of melanin so that pigmentation reduces

Why Niacinamide Is Less Likely to Trigger Purging

No Cell Turnover Acceleration

Can niacinamide cause purging? Purging occurs when the old skin cells are shed, and new ones form at a faster pace. Niacinamide has no effect on this process. It works on controlling oil and improving barrier function. It does not work on exfoliation or renewal rate. There is no mechanism through which Niacinamide could cause purging without accelerating cell turnover.

Regulates Sebum, Doesn't Exfoliate

Niacinamide signals the sebaceous glands to produce less oil over time, whereas salicylic acid dissolves the sebum inside pores, and AHAs dissolve the bonds between dead skin cells. It reduces the congestion that leads to breakouts. Niacinamide for pimples works by calming the conditions that create them.

Reduces Inflammation Instead

The anti-inflammatory action of Niacinamide calms the redness and swelling around active breakouts. So, does niacinamide cause pimples? Its inflammation-reducing properties make it the safest active for acne-prone skin, which you can introduce at any concentration between 5% and 12%.

What Could Actually Be Causing Your Purging

If you started a niacinamide product and broke out, here are the more likely reasons for it.

New Product Adjustment

Any new skincare product can cause a temporary adjustment period as your skin gets used to a new formula or ingredients. This is not purging, but your skin reacting to change. It settles within one to two weeks if the formula is compatible with your skin.

Reaction to Other Formula Ingredients

Many niacinamide serums contain additional actives, such as AHAs, BHAs, Retinol, or exfoliating enzymes, which increase cell turnover in your skin. If your Niacinamide serum contains these ingredients as well, the purging may result from them. So, always check the full ingredient list before blaming a reaction on any single ingredient.

Wrong Concentration for Your Skin

Using a 20% Niacinamide formula directly when your skin has never used actives before can cause irritation that looks like a breakout. It's your skin reacting to a concentration that it is not ready for. A safe way is to start between 5% and 10% and build up slowly to prevent flare-ups.

How to Add Niacinamide Properly to Your Skincare Routine

The chances of a reaction reduce a lot when you introduce Niacinamide correctly.

1. Patch test first: Take a small amount and apply it to your inner arm or jawline, and observe for any reaction in the next 24 hours before using it on your full face. Gentle ingredients can react differently on certain skin types, so you must do a patch test.

2. Start at a lower concentration: 5% to 10% is the best starting point if you are a beginner. Give your skin four weeks at this level before going with anything stronger.

3. Introduce one product at a time: If you add multiple new products all at once, you will never know which one is causing a reaction. Add Niacinamide on its own first and give it two to three weeks before introducing other active ingredients.

4. Apply after washing your face: Niacinamide works best when the skin is fresh. Apply it after your face wash and before your moisturizer so that it absorbs better into the skin.

5. Be consistent: The oil-regulating and pore-refining benefits of Niacinamide show only after four to eight weeks of daily use. So, you may not get the results if you stop using it abruptly because of an unrelated reaction.

Conclusion

If you are still wondering, does niacinamide cause purging? It does not. An increase in cell turnover results in purging, and Niacinamide does not work that way. The main reasons for breakouts can be your skin trying to adjust to a new product or another active ingredient in the formula. Higher concentrations can also be tough for your skin to tolerate, which may result in breakouts.

Researchers have found that up to 25 per cent more adults could be classified as obese, even if their body mass index (BMI) score falls under the normal category. As per the current rules, a BMI score of 18.5 to 25 is considered healthy, 25–29 is overweight, and 30 onwards is considered obese. Obesity can contribute to a long-term risk of serious illness, but according to an international team of experts, BMI may not be the most reliable measure for ascertaining obesity levels in an individual.

Why is BMI not a reliable parameter?

Researchers have found that adding the weight-to-height ratio and waist circumference could be a good way to ascertain unhealthy body fat levels. Fat, according to scientists, builds up in people who are not considered overweight or obese under the current rules, depending on where it is stored. Older bodies have a higher fat build-up around the waist, which, when combined with loss of muscle mass, means that there is no change in total weight. This means that the fat that accumulates, known as "skinny fat," does not always raise an alarm.

The new study from scientists at the University of Southern California analysed data from 5,642 adults in the US and discovered that a quarter of them had a normal BMI but actually met the obesity criteria. Furthermore, over 50 per cent of overweight people, according to their BMI, also met the updated obesity criteria. These findings, according to experts, suggest that millions of Americans with obesity-related health complications could be missing much-needed health interventions.

BMI is problematic because it does not evaluate body fat but reflects total body weight, including muscle and bone. Therefore, a muscular person is likely to have a high BMI but not much fat. However, a person with a normal BMI can have excess body fat, which can lead to complications later. The good news, experts say, is that these obesity-related issues can be addressed. Either lifestyle changes, medication, or both can be effective in reducing body fat levels and lowering the risk of future health problems. The sooner it is diagnosed, the better it is for long-term well-being.

Read more: Why 'Normal Weight' Doesn’t Always Mean Healthy

Does obesity risk increase with age?

Researchers estimate that 30 per cent of adults living in England aged 16 years and above are obese. This increases with age, with over 35 per cent of people aged 55 to 74 years living with obesity. Under the new rules, obesity would be defined as a BMI of 30 and above, or at least one elevated measure, such as a high waist circumference, a high waist-to-height ratio, or a BMI of 40 and above. Researchers have labelled these obesity subtypes as BMI-plus-anthropometric obesity.

What is an unhealthy waist circumference?

According to the NHS, an unhealthy waist circumference is 37 inches in men and 31.5 inches or above in women. An unhealthy waist-to-height ratio occurs when the waist circumference is half or more of a person's height. According to the British Heart Foundation, BMI is calculated by dividing weight by height squared. There are multiple BMI calculators available online. It is classified as follows:

1. Underweight – below 18.5
2. Healthy weight – 18.5 to 24.9
3. Overweight – 25 to 29.9
4. Obese – 30 and above

If BMI is in the overweight category, it is linked with a heightened risk of heart disease and incidents such as stroke or heart attack. If it falls within the obese category, the risks are higher. Underweight people are not exempt from risk, as they have a greater likelihood of developing long-term health problems.