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Do dogs lose weight during heat?

Do dogs lose weight during heat?

If you’ve never cared for a female dog previously, you may be caught off guard by sudden changes in their behavior. Seemingly out of the blue, your pet may start to become more restless. She may try to run out your front door even though she hasn’t done that before.

The changes in behavior may seem very strange, but there could be a simple explanation for them. Those changes in your pet’s behavior could be because she is currently in heat.

Changes brought about by a heat cycle can be quite varied. They can affect several aspects of your dog’s behavior.

Will those changes affect your pet’s weight as well? Find out the answer to that question by reading on.

Do Dogs Lose Weight during Heat?

Whether or not a dog will lose weight during her heat cycle is not set in stone. That will be determined by how much your dog’s habits will change while she is in heat.

You see, female dogs change when they are going through their heat cycle. While in heat, your pet will only care about mating. Her urge to mate may become so strong that it completely overrides everything else.

Playtime may take a backseat to her mating desires. Even her eating habits may change.

The heat cycle is part of the reason why your pet is losing weight. Her fixation on mating and lack of interest in eating may also be driving her weight loss.

Do Dogs Lose Their Appetite while in Heat?

Yes, it is possible for your dog to lose their appetite while in heat. Because your dog has become so fixated on mating, they will not care as much about eating.

Do not be surprised if your dog ignores the food you served altogether. All she may want to do is head out and search for a mate so may just ignore the food.

It’s also possible that your dog only seemingly loses her appetite during certain times of the day. She may be hungry and eager to eat in the morning, but less reluctant to chow down at night.

That odd behavior could be a result of your dog becoming less active. Some female dogs become lethargic while in heat. Because they aren’t expending that much energy throughout the day, they may also be less hungry at night.

Why Is My Dog in Heat Not Eating?

A female dog losing her appetite while going through her heat cycle is normal. You have nothing to worry about there.

However, there may be a problem if your dog stops eating altogether. Try to entice your dog to eat by offering her favorite treats. You can also keep her indoors for a while so she isn’t distracted by any male dogs nearby.

If your dog is still not eating at all after doing those things, then there is likely a more serious issue affecting her. Take her to the veterinarian as soon as you can and get her checked out.

Her heat cycle may have just been masking the real reason why she lost her appetite. In reality, an illness may be causing that problem.

Do Dogs Lose Weight during Summer?

The summer heat can be tough for some dogs to deal with, but is it so oppressive that it can cause your dog to lose weight? The heat itself may not be the cause of the weight loss. Instead, the weight loss may be a byproduct of changes in your dog’s routine.

For example, a lot of folks go out more with their pets during the summer. Since your dog is more active, they are also more likely to shed some weight.

You should also check if the heat is proving too much for your dog. They may lack the energy to eat because the summer heat is overwhelming them.

Help your dog cool down by changing their water regularly and brushing their coat. They may start to eat regularly again after you do those things.

What Are Signs That My Dog Is in Heat?

Knowing when your dog is in heat is helpful if you want to understand why they are acting strangely. You will be able to avoid panicking and stressing out over your dog.

So, how can you tell if your dog is in heat? There are some signs to watch out for and we’ve detailed them below.

Bloody Discharge from the Vulva

The first sign you’ll probably notice is some bloody discharge from the vulva. That’s because the bloody discharge will likely be visible on the floor or your dog’s bed.

Note that the discharge may not always be red. It can also have a yellowish or brownish color. The discharge may even feature a mixture of brown, red, and yellow colors.

Frequent Licking of the Genital Area

Dogs in heat will lick the area near their genitals are more frequently. Keep an eye out for this habit if you suspect that your pet is going through her cycle.

Frequent Urination

Aside from licking their genital area more often, dogs in heat may also have to urinate more frequently. This change is easier to notice because you’ll have to take your dog out more often.

Swollen Vulva

If you already suspect that your dog is in heat, you can examine her vulva to confirm that. Her vulva will be swollen if she is indeed going through her heat cycle. The vulva may also appear redder in color.

Behavioral Changes

We already mentioned it earlier, but dogs going through their heat cycle may change their behavior. The behavioral changes can manifest themselves in different ways.

Dogs in heat may want to go out more. They may even try to run outside your home whenever someone opens the door.

While outside, your pet may also approach other dogs. She may approach male dogs in particular.

Your pet may also grow anxious and agitated during that time if they are unable to meet. Try to comfort them as much as possible to ease them through that period.

Why Is My Dog Losing Weight Suddenly?

Sudden weight loss in dogs can be a troubling sign. You’ll understand why after you learn more about the potential explanations for your dog’s sudden weight loss.


Your dog losing weight could be because they are currently dealing with an illness. Numerous ailments can cause weight loss in our furry friends. Serious illnesses such as cancer and diabetes are potential explanations. Issues with the liver or kidneys can explain the weight loss too.


Parasites living inside your dog’s body can absorb important nutrients. Your dog may not receive as much nutrition from the food you’re serving because the parasites are in the way.

Dental Issues

Issues related to their mouth, tongue, or teeth can make eating extremely uncomfortable for dogs. If you notice them growing uncomfortable while eating, those dental issues may be to blame.

Changes to Their Food

Your dog may not adjust right away to their new food. They may not eat as much while they’re getting used to it and that could explain their weight loss.

Also, the new food you’re serving may not be very nutritious. Your dog may lose weight if they continue to eat that exclusively.


Lastly, stress can explain why your dog has lost weight. Moving to a new home or sharing their home with a new pet may be stressing out your dog. All that stress may be having an adverse effect on their appetite.

Give your dog some time to adjust and comfort them too. Before long, their eating habits will normalize and they will return to their previous weight.