Skincare Myths That Persist Despite the Evidence

Pores are simply openings in the skin through which hair follicles and sebaceous glands reach the surface. They have no muscular structure and do not respond to steam or cold water by physically expanding or contracting. Hot water may temporarily make pores appear larger by softening the debris inside them, and cold water may cause mild tissue contraction — but neither changes actual pore size. Genetics, age, and sun damage are the main determinants of how prominent pores appear.

Poison ivy is natural. So is lemon juice, which can cause phototoxic burns when applied to skin exposed to sunlight. Essential oils, botanical extracts, and natural fragrances are among the most common causes of contact dermatitis documented in dermatology literature. Meanwhile, many synthetic ingredients — such as niacinamide or hyaluronic acid — have extensive safety profiles and are well tolerated across skin types. What matters is the ingredient's safety data, concentration, and formulation, not whether it came from a plant or a lab.

Staying adequately hydrated is important for overall health, and severe dehydration can affect skin elasticity. However, drinking extra water beyond normal hydration needs does not measurably increase moisture in the outermost layer of skin — the stratum corneum — which is primarily maintained by the skin barrier itself, topical humectants, and environmental humidity. Topical moisturizers and ingredients like ceramides or glycerin are far more directly effective at supporting surface hydration than increasing water intake. For more on this distinction, see common myths about drinking water and hydration.

SPF ratings on products are determined using a standardized application amount of 2 milligrams per square centimeter of skin. Studies have shown that people apply makeup at a fraction of that quantity — often one-quarter or less — which dramatically reduces the effective SPF. Additionally, makeup is rarely reapplied throughout the day the way sunscreen should be. SPF in foundation can contribute to protection at the margins, but it should not be treated as a substitute for a dedicated, properly applied broad-spectrum sunscreen.

The cost of a skincare product reflects packaging, branding, marketing, and retail positioning as much as it reflects ingredient quality. Many active ingredients — retinol, niacinamide, glycolic acid, zinc-based sunscreens — are widely available across price points. What determines efficacy is the concentration of the active ingredient, its stability in the formula, and whether it is paired with compatible ingredients. A dermatologist-reviewed, modestly priced product with evidence-backed actives can outperform a luxury alternative with weaker formulation.