What Do Moths Really Eat

Moths are often seen as pests, fluttering around lights and ruining our clothes. But have you ever wondered what these insects actually eat? In this article, we’ll explore the diet of moths, specifically the luna moth, and debunk some common misconceptions.

The Diet of Moths

Contrary to popular belief, moths do not eat clothes. In fact, most adult moths do not eat at all. They rely on the energy stored from when they were caterpillars to survive. However, there are some exceptions to this rule.

Adult Moths

Moth on flowerby Aaron Burden (https://unsplash.com/@aaronburden)

As mentioned, most adult moths do not eat. This is because their main purpose as adults is to reproduce and continue the life cycle. They have evolved to have a short lifespan, with some species only living for a few days. Therefore, they do not have a need for food.

However, there are some exceptions to this rule. Some adult moths, such as the luna moth, do have a short lifespan but still need to eat during that time. These moths will feed on nectar from flowers, using their long proboscis (a straw-like mouthpart) to suck up the sweet liquid. This is their main source of energy and allows them to mate and lay eggs before they die.


Caterpillars, on the other hand, have a very different diet from adult moths. They are voracious eaters and will consume large amounts of leaves, flowers, and even other insects. The specific diet of a caterpillar depends on the species of moth it will eventually become.

For example, the luna moth caterpillar feeds on the leaves of various trees, including birch, hickory, and walnut. They are also known to eat leaves from fruit trees, such as apple and cherry trees. This diet provides them with the necessary nutrients to grow and eventually transform into an adult moth.

The Diet of the Luna Moth

The luna moth (Actias luna) is a beautiful and iconic species of moth found in North America. It is known for its large, green wings and long, delicate tails. But what do these moths eat?

Adult Luna Moths

As mentioned, adult luna moths feed on nectar from flowers. They are most active at night and are attracted to white or light-colored flowers, such as jasmine, honeysuckle, and petunias. They use their keen sense of smell to locate these flowers and then use their proboscis to extract the nectar.

Luna Moth Caterpillars

Luna moth caterpillarby Wyxina Tresse (https://unsplash.com/@wyxina)

The diet of luna moth caterpillars is quite specific. They only feed on the leaves of certain trees, including birch, hickory, and walnut. This is because these trees contain a chemical called juglone, which is toxic to most insects but not to luna moth caterpillars. This gives them a competitive advantage over other caterpillars and allows them to thrive.

Interestingly, luna moth caterpillars also have a unique way of eating. They do not chew on the leaves like most caterpillars do. Instead, they use their sharp mandibles to cut through the leaves, creating a clean, circular hole. This method of feeding is thought to help them avoid detection by predators.

Common Misconceptions About Moth Diets

There are many misconceptions about what moths eat, and these can often lead to fear and misunderstanding of these insects. Let’s debunk some of the most common myths about moth diets.

Moths Eat Clothes

One of the most widespread myths about moths is that they eat clothes. This is not entirely true. While some species of moths, such as the webbing clothes moth, do feed on natural fibers like wool and silk, they do not actually eat the fabric itself. Instead, they feed on the keratin found in these fibers, which is a protein also found in hair and nails.

Moths Are Harmful to Plants

Another common misconception is that moths are harmful to plants. While it is true that some moth caterpillars can cause damage to plants, this is not always the case. In fact, many moth species are important pollinators and play a crucial role in the ecosystem.

All Moths Have the Same Diet

Moths on flowersby Rodion Kutsaiev (https://unsplash.com/@frostroomhead)

There are over 160,000 species of moths in the world, and each one has a unique diet. While some may feed on nectar, others may feed on leaves, fruits, or even other insects. It is important to understand the specific diet of each species to fully appreciate their role in the ecosystem.


In conclusion, moths have a varied and interesting diet. While most adult moths do not eat at all, some species, such as the luna moth, do feed on nectar from flowers. Their caterpillars, on the other hand, have a very specific diet, with the luna moth caterpillar only feeding on the leaves of certain trees. It is important to understand the diet of moths to appreciate their role in the ecosystem and debunk common misconceptions.