Where should I consult about beauty supplements and how to choose? A good benchmark is whether they ask about medications you're taking and your test results.

A good benchmark for choosing beauty supplements is to select them at a place that explains the research differences by ingredient and asks about medications you're currently taking and their effects on blood tests.[1][2]. Supplements are sold without the strict verification required for pharmaceuticals, making drug interactions and effects on test values easy to overlook.[1]. Some ingredients like collagen have extensive research, while others show no difference.[2].

Do they explain the research differences by ingredient?

First, look for whether they discuss how the strength of evidence differs by ingredient. An analysis of 14 studies and 967 people on collagen showed improvements in skin moisture and elasticity in about 12 weeks.[3].

In a 70-person trial, people who took collagen for 8 weeks showed improvements in wrinkles, elasticity, and moisture, which persisted 2 weeks after stopping.[4]. On the other hand, an analysis of 40 trials found no clear difference for hyaluronic acid and lycopene against sun-induced skin aging (photoaging).[2].

Do they ask about medications you're currently taking first?

Pre-confirmation is especially important for people taking medications. About half of those using prescription drugs are reported to also continue taking supplements, and harm increases with more medications.[5].

People taking 3 or more prescription drugs often use supplements, raising concerns about drug interactions.[1]. It is also recommended to consult with a specialist before buying supplements to confirm your physical condition.[6].

Do they discuss blood tests and risks of overdose?

Some supplements can shift test values or accumulate in the body if taken in excess. For example, biotin taken for hair and nails can affect blood test values for the thyroid and heart.[1].

Excess zinc can make it harder to absorb other minerals like copper.[1]. Vitamins A and E are not excreted in urine, so excess can accumulate and cause harm.[1]. Before a health checkup, tell your doctor about the supplements you're taking.

Reports of liver problems from herbs and supplements are also increasing, particularly in people with liver disease.[7]. If you have ever been told you have liver disease, you must disclose it.

Who is it for? "People with deficiencies" benefit most easily.

The effect of nutritional supplementation is said to be greatest in people who are already deficient.[8]. Conversely, except for those who are truly deficient, many supplements have weak evidence.[1].

For this reason, the deciding factor is whether they listen to your diet and concerns, then think through with you whether you need to take them. Most research examined periods of 24 weeks or less, and safety during that period is reported, but the long-term effects of continued use remain unclear.[2].

Where should I choose? A benchmark when unsure.

During consultation, ask about the following points.

Evidence: Do they explain what research has shown for each ingredient?[3][2]

Drug interactions: Do they confirm medications you're taking and other supplements?[1][5]

Tests and overdose: Is there an explanation of effects on test values and ingredients that accumulate?[1]

Necessity: Do they think through with you whether you need it based on your diet and physical condition?[8]

Which supplement is right for you cannot be decided from an article alone. In consultation, tell your doctor about medications you take, any chronic conditions, and skin concerns you have, and decide together on the duration and when to stop.