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Do dogs gain weight during heat?

Do dogs gain weight during heat?

When a dog is in heat, she may go through many different biological processes. If you’re not used to her cycle or it’s your pup’s first estrus, you may be wondering if your dog will gain weight during heat.

There are many factors to consider when assessing your dog’s weight, including age, breed, and activity level. Read on to learn more about how a dog’s body changes during estrus and whether or not she will gain weight.

Do Dogs Gain Weight During Heat?

Some dogs may experience a slight weight gain during their heat cycle due to an increase in water intake and blood volume. However, most dogs will not gain any noticeable weight.

If you keep your dog’s food intake and exercise routine consistent, you should not see a significant change in her weight during heat.

Your dog may appear to have gained some weight if she is holding water weight or if her cycle is longer than usual. Especially if it’s early on in her cycle, she may be experiencing some stress and fatigue during this time.

There are a few things you can do to help your dog stay healthy and comfortable during her heat cycle:

  • Make sure she has plenty of fresh water available at all times.
  • Avoid strenuous exercise, especially in hot weather.
  • If your dog is panting excessively or appears to be nauseous, contact your vet right away.
  • Create a comfortable environment for her to rest in.
  • Give her extra love and attention.

These tips will help you keep your dog healthy and happy during her heat cycle.

Why Is My Dog in Heat Eating So Much?

It’s common for a dog’s appetite to increase during her estrus cycle. This is due to the increase in hormones that are released during this time.

Your dog’s increased appetite should not cause her to gain excessive weight, as long as you continue to provide her with a healthy diet and regular exercise.

If your dog is eating more than usual, make sure she has access to plenty of fresh water and provide her with a high-quality, nutritionally balanced diet.

The most nutritional diet for your dog includes high-quality protein, whole grains and veggies, and omega fatty acids for a healthy coat and skin. Vitamins, minerals, antioxidants, and probiotics are also important for immune system support.  

Be careful not to overfeed “human” food to your dog. While a little bit of table food is okay, too much can upset her digestive system and lead to weight gain. The high-fat content, as well as the processed ingredients in many table foods, can be harmful to your dog’s system.

If you are concerned about your pet gaining weight during heat or if her appetite is out of the ordinary, contact your vet for advice. Your veterinarian will recommend appropriate nutritional changes and support healthy changes within the normal home environment where you continue to provide love and affection throughout this cycle.

Why Is My Dog Suddenly Gaining Weight?

There are many reasons why a dog may suddenly gain weight, and the cause should be determined by a veterinarian.

Some common causes of sudden weight gain in dogs include:

A Change in Physical Activity Level

If your dog has had a significant change in it’s activity level, this could lead to rapid weight gain. This may happen if your dog doesn’t get regular walks or outdoor time.

If your dog’s playmates, such as a child that played with your dog regularly or another animal in the house, moves away, your dog may become inactive and gain weight as well.

Find ways that can engage your dog in physical activity, even if it’s just playing around indoors. Interactive toys and games are a great way to keep your dog entertained and active.

If there isn’t enough time in your schedule but funds are available, consider hiring a dog walker so that your dog can get the exercise she needs.

A Change in Diet

If there has been a change in your dog’s diet, this could be causing her to gain weight. This may happen if you switch to a food that is high in calories or fat. You may have also changed the amount of food you’re feeding your dog which could be causing weight gain.

Another reason for a change in your dog’s diet may be that you are feeding table scraps or giving your dog a large amount of treats in addition to her regular food.

If there are other pets in the house, your pup may be eating their food as well.

Make sure to give your dog a high-quality, nutritionally balanced diet that meets her needs for daily caloric intake. If you’ve made changes to your dog’s diet, slowly transition back to the original food over a period of a week or two. This will help avoid an upset stomach and other digestive issues.

Genetic Factors

Some dogs are just prone to weight gain and no matter what you do, they will always be a little on the heavy side. This is often seen in larger breeds of dogs.

A dog’s weight may also be affected by her family line, so if your pup is gaining a lot of weight, ask your veterinarian if there are any genes in her family history that may be influencing weight gain.

Spaying or Neutering

Spaying or neutering your dog can also cause her to gain weight. This is because when a female dog is spayed, the number of calories she needs is reduced in order to maintain a healthy body weight.

The same goes for neutered male dogs, as testosterone helps regulate energy and metabolism.

If you have recently spayed or neutered your dog, make sure to speak with your veterinarian about the appropriate diet and amount of food to keep your dog in a healthy body condition.

Aging Dogs

When dogs get older, they naturally begin to lose muscle mass and gain weight. This is a normal part of the aging process in canines.

This doesn’t mean that you should allow your senior dog to become overweight because it could lead to many problems associated with excess pounds such as arthritis or diabetes. There are certain things you can do that will help to keep your dog healthy as she ages, including feeding her a senior-specific diet and ensuring she gets plenty of modified exercise.

Side Effects From Prescriptions

Another potential cause of weight gain in dogs is medication, particularly if your dog has recently started a new prescription. Some common side effects of medications include increased thirst and appetite, which could cause your dog to gain weight.

If you notice that your pup has gained a few pounds recently or is looking more overweight than usual, it may be because of the medication she’s taking. Speak with your veterinarian about switching medications to alleviate this side effect.

Water Retention

Water retention, also known as edema, is a condition that can cause dogs to gain weight quickly. This happens when fluid accumulates in the tissues and cells, often because of an underlying health problem.

Some underlying causes include kidney or liver disease, heart failure and Cushing’s Disease. If you notice that your pet is gaining weight without any explanation such as changes in diet, talk to your veterinarian about potential causes of water retention which can help identify the right treatment plan for your pup.

Cushing’s Disease

Cushing’s disease is a hormonal disorder that can cause dogs to gain weight, among other things. One of the most common symptoms of Cushing’s Disease is an increase in appetite and a tendency to gain weight easily.

This disease is caused by too much cortisol in the bloodstream, which is often the result of taking certain medications or getting injections of steroids. If you notice your dog is gaining weight and you suspect Cushing’s Disease, speak with your veterinarian about getting a cortisol test.


Diabetes is a serious health condition that can cause dogs to have excessive weight gain. This happens because the body is unable to use glucose (sugar) for energy, so the dog begins to store it as fat.

Some common symptoms of diabetes include excessive thirst and urination, weight fluctuations, and fatigue. If you think your dog may have diabetes, please take her to see your veterinarian right away for diagnosis and treatment.


Hypothyroidism is a condition that can cause dogs to gain weight, among other things. This disease is caused by low levels of thyroid hormone in the bloodstream, which reduces your pup’s metabolism and causes her to gain weight.

Some common symptoms of hypothyroidism include a decrease in energy, hair loss, and weight gain. Hypothyroidism is corrected with medication, so if you suspect your dog may have this disease, take her to see your veterinarian to correct this imbalance.

What Are Common Side Effects for a Dog in Heat?

When a dog is in her estrus cycle, there are some common side effects that may occur. These can include:

Frequent Urination

One of the most common side effects for a dog in heat is frequent urination. This happens because her body is trying to release as much urine as possible during this time, so she’ll go often and may even have accidents indoors.

Swollen Vulva or Bleeding from Vagina

In some cases, your pup’s vulva will become swollen and may even bleed as a result of the increased blood flow. This is normal and will usually go away within a few days.

Change In Appetite

Some dogs will lose their appetite during the estrus cycle, while others may find themselves with an insatiable craving for food. If your dog is losing her appetite or suddenly wants to eat everything in sight, this could be a sign of hormone fluctuations as she goes through her heat cycle.

Do Dogs Gain Weight When the Weather Is Hotter?

As the weather starts to heat up, it can be tempting for us humans to start shedding some layers. However, if you notice that your dog is putting on weight even though she’s not eating more than usual or exercising less, this might mean that there’s a problem with her metabolism and hormone levels because of the hot temperatures.

In order to cool down, dogs will often pant and drink more water. This can lead to them gaining weight or holding onto water weight as they take in more fluids than they’re expelling.

Do Dogs Bloat During Heat?

Dogs who are in heat might bloat as their blood vessels expand and circulation becomes more rapid.

The swelling that happens is primarily in the vulva area, and the amount of bloat will vary depending on a dog’s breed, age, and size.

There shouldn’t be excessive bloating in dogs during heat. However, some dogs may experience a mild weight gain that can be attributed to bloating or an increased appetite.