Selecting a laundry detergent

Hundreds of millions of dollars have been spent in an effort to get you to purchase and use certain kinds of laundry detergent, based on claims of superior cleaning performance, color safeness, gentleness for delicates, scent, color, powder versus liquid, and ability to clean in cold water. With the shelves overflowing with brands and versions of detergent, how can we make an informed choice?

We're going to look at detergents from several angles: powder versus liquid, how detergents work, other functions of detergents, other laundry chemicals, and why you might not be getting the best performance from your current detergent. When we're done, you should be able to more easily choose an appropriate detergent and get your laundry as clean as possible.


POWDER: The first laundry powders were actually flakes of soap. These flakes left a dingy gray film on clothes, and it didn't do a very good job taking stains away from clothes.

Synthetic powder detergents came next, and soap flakes quickly left the market, because detergents did what soap could not: it removed stains, suspended soil for improved rinsing, and rinsed clean without leaving residues. Powders also allowed detergent manufacturers to add brightening agents, soil suspending agents, water softeners and soil supsending agents (non-ionic surfactants), perfumes, fabric softeners, and color-safe bleach without reducing efficacy.

LIQUID: Liquid detergents emerged after powders, and originally were not as effective as powders. However, in the last 5-10 years, liquids have evened the score and now perform as well as powders in almost every regard. Liquid detergents are only limited by chemistry, as the detergent must remain a single homogenous liquid, and as more chemicals are added, the harder it becomes to keep them all combined. Advances in chemistry have resulted in liquid detergents that can do everything powders do.

Whether you choose liquid or powder, your results should be consistent as long as you follow the washing machine manufacturer's instructions for adding detergent.


Detergents break down the surface tension of water, making it "wetter." They also make stains attractive to water molecules, which allows them to be drawn off of clothes and prevented from redepositing. Scientifically, this is a simultaneous hydrophilic/hydrophobic action within the detergent caused by non-ionic surfactants that emulsifies oil-based stains by enveloping stain molecules with water molecules. Colloquially, it's called cleaning your clothes.

Many detergents also have enzymes, which are little microorganisms that eat the stains in your clothes. These microorganisms don't harm your fabrics, and are one of the big reasons pre-treating stains with detergent helps with stain removal. The longer they have to work on the stain, the more effectively the stain is removed.

Some detergents have sudsing agents that create suds. If your detergent does not have the HE symbol ("he" in an oval), it has sudsing ingredients. These chemicals started getting added when marketers discovered that American consumers who see suds in their soapy water believe there is greater cleansing occurring than in soapy water without suds. Suds are not, however, proof of cleansing; they are just bubbles, and are evidence of the presence of some sort of glyceride and water softening agent. We'll go further into suds in the ACHIEVING OPTIMAL PERFORMANCE section further down.


Detergents are also used to impart scents onto clothes. Perfumes are added to the detergent to create flowery, soapy, or fruity aromas. Scent, however, has nothing to do with cleanliness, as anyone who's sprayed on perfume or cologne after rigorous exercise can attest.

Many detergents have dyes in them, most often a colorant called "bluing." This colorant is, as the name implies, blue, and it counteracts the yellowing that occurs on white clothes as a result of bleaching, sweat, or deterioration. Just like snow looks extra white because of the reflection of blue from the sky, whites look whiter with a hint of blue, and look dirtier when they're yellowed. This is why so many liquid detergents are blue, or have blue as a component of its color.

Some detergents have fabric softeners added, so you don't have to remember to add it for the rinse cycle. Others will have color-safe bleach (usually hydrogen peroxide or hydrogen perborate, combined with enzymes and optical brighteners) to whiten whites and brighten colors.

Some detergents, however, are designed to be free of dyes and perfumes. These were originally designed for people with allergies to perfumes or dyes, but have become popular among a broad range of people with and without allergies. Cleaning performance is not compromised by lacking these chemicals, and those who are bothered by them can enjoy clean clothes without allergic reactions.


Baking Soda: sodium bicarbonate; helps neutralize the pH of water to enhance effectiveness of detergent and bleach; also used as an odor eliminator

Bleach: a solution of sodium hypochlorite and water, sometimes with perfumes added; bleach cleans by whitening stains and oxidizing the fabric; also kills bacteria

Bluing: blue colorant that increases intensity of whiteness by counteracting yellowing caused by bleaching, sweat, or deterioration

Borax: a combination of boric acid and water softeners that increase cleaning ability of detergents

Color-safe bleach: sodium peroxide/perborate, optical brighteners, enzymes, and perfume

Fabric softener: an oil or silicone-based compound added to detergents, bottled separately in liquid form, or infused onto sheets, that behaves like hair conditioner on hair by lubricating the surface of fibers that would otherwise feel coarse to the touch; also reduced static electricity by inhibiting escape of electrons

Non-ionic surfactants: chemicals added to detergents that allow stain molecules to be enveloped by water molecules

Optical brighteners:
reflective compounds added to detergents to make colors appear brighter (these create phosphorescence under a black light)


First, if you're using regular detergent, I recommend switching to high-efficiency (HE) detergent. Why switch? Well, it is compatible with every washing machine on the market, costs the same as regular, and will rinse cleaner because it has no sudsing ingredients.

Regular detergent with lots of suds is the reason conventional washing machines have such thoroughly drenching rinse cycles. It's not to get rid of the suspended stains or the detergent; it's to flush away all the suds from the clothes. In fact, most conventional washers actually have two rinses because the first rinse actually creates some suds while it flushes them away. By preventing suds in the first place, your washer will rinse your clothes cleaner than ever.

Second, you should follow the washing machine manufacturer's instructions for adding detergent. For conventional machines, this usually means starting the cycle, adding detergent to the tub as it fills, and then adding clothes. This is probably exactly what you're not doing, as the vast majority of Americans throw their clothes into an empty washtub, add detergent to the top of the pile, then turn on the washer. This results in poor detergent distribution, sub-standard dissolution of powder detergents, and lackluster cleaning performance. For HE machines, this means adding detergent to the appropriate dispenser.

Third, don't overdose your laundry. Detergent's cleaning action does not increase as the dosage increases. In fact, it actually cleans worse when excessive detergent is used. Follow the detergent manufacturer's instructions for dosing, and use a little less than you think it needs. This will almost always give you the best results.

Fourth, avoid using fabric softener in the washer, as it's not very good for the machine. If you do use it in the washer, dilute it before adding it to the dispenser. If your washer does not have a fabric softener dispenser, do not add it at the beginning of the cycle, as it will prevent the detergent from being able to clean and will leave you with dirty clothes for your trouble. Softener must be added at the beginning of the rinse cycle, so only a thin residue is left on the clothes at the end of rinsing. Because it's inconvenient and difficult to remember to do this, I recommend using dryer sheets instead.

Fifth, sometimes you do get what you pay for, but sometimes you don't. For instance, Tide HE detergent works very well, but Sears UltraPlus detergent works extremely well, has bleach alternative, fabric softener, Oxi Clean, and dye/perfume free versions in addition to the regular version, all available in either liquid or powder, and at a much lower per-washload price than Tide.

Sixth, because enzymes in detergent work better as the temperature increases, be sure to use at least the "cool" or "cold" setting. If you live in an area that has cold winters (regularly under 30 degrees Fahrenheit), don't use the "cold" or "tap cold" settings in the winter, as the water is likely to be too cold for the detergent to be effective.