Berries

Berries are widely recognized for their antioxidant, anti-inflammatory, and nutrient-rich properties, making them a great addition to your dog's diet. While blueberries are often highlighted for their impressive benefits, many other berries, such as strawberries, raspberries, cranberries, and blackberries, offer similar advantages.

Studies involving berries for dogs

Blueberries And Oxidative Stress In Dogs

In a study published in the journal Comparative Biochemistry and Physiology, researchers examined the effects of blueberries in sled dogs after exercise. They observed that dogs supplemented with blueberries had significantly higher antioxidant levels, suggesting that blueberries may help protect against exercise-induced oxidative damage (Dunlap et al., 2006).

Blueberries and Service Dogs

Another study conducted in Italy divided service dogs into two groups. Both groups consumed a kibble-based diet, but one group was supplemented with blueberries and other berries. After 18 weeks, the dogs receiving berries had lower markers of oxidative stress. There was also a significant reduction in oxidative stress, further supporting the antioxidant benefits of berries in canine diets (Mancini et al., 2019).

In another animal study, blueberries exhibited anti-inflammatory properties in rats affected with post-traumatic stress disorder (PTSD). Researchers noted that biological inflammatory markers were lower once blueberries were consumed, with results suggesting that blueberries may help restore neurotransmitter imbalances.

A study on older humans showed eating 2 cups of blueberries a day improved mobility. In other trials, people who drank blueberry juice had lower blood sugar levels. 

More research cited by Dana Scott 

“Human studies show children do better on cognitive tests after eating blueberries. They show “dietary blueberry” improves cognition in older humans.  Another study showed that mice eating blueberries were less likely to develop Alzheimer’s disease. And one showed pro-inflammatory genes in aged rats were reduced to the levels of young rats.”

Cranberries and Urinary Tract Health

Cranberries have long been associated with urinary tract health in both humans and animals. A study published in the American Journal of Veterinary Research found that supplementation with cranberry extract reduced the adhesion of bacteria to the bladder wall, potentially preventing urinary tract infections (UTIs) in dogs (Pappas et al., 2014).

Strawberries and Anti-Inflammatory Effects

Strawberries are rich in antioxidants and polyphenols that provide anti-inflammatory benefits. While direct studies in dogs are limited, research in other species suggests that strawberry consumption may reduce inflammation and oxidative stress. These benefits could extend to dogs, supporting overall health and longevity (Basu et al., 2010).

Raspberries and Cognitive Function

Raspberries are high in anthocyanins and flavonoids, compounds known to improve cognitive function. A study in aged rats found that diets supplemented with berries, including raspberries, improved motor skills and memory function, suggesting potential cognitive benefits for dogs as well (Shukitt-Hale et al., 2012).

Nutritional Benefits of Berries for Dogs

Berries offer a range of essential nutrients that contribute to canine health. Here are some of the key nutrients found in berries and their benefits for dogs:

• Carotenoids: These pigments, including beta-carotene, support immune function and eye health.

• Fibre: Promotes healthy digestion, weight management, and blood sugar control.

• Folate: Crucial for metabolism, cell growth, and maintaining healthy cell membranes.

• Vitamin C: A powerful antioxidant that neutralizes free radicals and supports immune health.

• Vitamin E: Essential for protecting cell membranes and preventing oxidative damage.

• Vitamin K: Supports blood clotting, bone metabolism, and calcium regulation.

• Potassium: Regulates nerve impulses, heart function, and muscle activity.

• Manganese: Assists in the digestion of carbohydrates and proteins, as well as enzyme activation.

• Magnesium: Supports over 300 metabolic processes, including nerve function, muscle activity, and blood sugar regulation.

• Iron: Essential for oxygen transport in the blood and preventing anemia.

• Riboflavin (Vitamin B2): Contributes to proper metabolism, nutrient absorption, and tissue maintenance.

• Niacin (Vitamin B3): Supports glucose, fatty acid, and amino acid metabolism.

• Phytoestrogens: Plant-based compounds that support thyroid function, skin health, and hormone balance.

Antioxidants and Their Role in Canine Health 

Berries, especially blueberries, are rich in polyphenols and flavonoids, which act as antioxidants to combat oxidative stress. Oxidation occurs when free radicals accumulate in the body, damaging cells and contributing to ageing, inflammation, and chronic diseases. Antioxidants help neutralize these harmful free radicals, reducing the risk of conditions such as:

1. Cardiovascular disease

2. Cancer

3. Cognitive decline

4. Diabetes

5. Arthritis

6. Kidney disease

Studies have shown that berries, particularly blueberries, contain unique antioxidants that help protect brain cells and may delay cognitive decline in dogs. These compounds also promote healthy blood sugar levels, support cardiovascular function, and protect against inflammation.

Antioxidants and Neutralising Oxidative stress  

Oxidation is the common cause of cellular damage and ageing. Over time, metabolic byproducts build up in your dog. These substances are called reactive oxygen species or free radicals. Free radicals amass in your dog’s cells and organs. Free radicals damage your dog’s cells. In fact, they’re the main cause of ageing and degenerative diseases.

The damage free radicals cause to the body is called oxidative stress. When free radicals build up in large amounts, they harm the cell membranes and even DNA. This leads to age-related diseases such as diabetes, arthritis and kidney disease. And the damage to DNA can lead to cell mutations and even cancer.

Free radicals aren’t only a byproduct of metabolism. They can also build up when your dog is exposed to toxins, pollution, chemicals and drugs even the foods your dog eats can also generate free radicals! The main offenders include foods containing preservatives, starches and rancid fats.

However, antioxidants can neutralize free radicals. So any food full of these beneficial compounds, like blueberries, will help combat the damaging effects of free radicals.

How to Safely Feed Berries to Dogs

Berries and cherries are a delicious, nutritious treat for dogs, but not all berries are safe for canine consumption. It’s important to be aware of which berries can be safely offered to your dog, especially when foraging for wild varieties or growing them in your garden. This guide includes common safe berries, as well as cautions when feeding, and a special focus on foraged and home-grown berries like Black Bryony, White Bryony, rose hips, elderberries, and hawthorn berries.

Key Guidelines for Feeding Berries and Cherries to Dogs

  1. Use Organic Berries: Opt for organic berries whenever possible. Organic berries are free from harmful pesticides and herbicides, reducing the risk of introducing toxins into your dog’s system.

  2. Moderation is Key: Berries should make up no more than 10% of your dog’s daily caloric intake. Overfeeding can cause digestive upset due to the high fibre content, leading to loose stools or constipation.

  3. Introduce Slowly: Always start with small amounts when introducing new foods to your dog’s diet. Gradually increase the amount, watching for any signs of digestive issues or sensitivities.

  4. Serving Suggestions:

    • Add whole berries to your dog’s meal.

    • Blend them into a smoothie with kefir or goat’s yoghurt.

    • Use them in homemade treats.

    • Freeze them for a cool, refreshing snack.

Home-Grown Berries for Dogs

If you’re growing your own berries, you have control over the cultivation process, ensuring they are free from harmful chemicals and pesticides. The following berries are generally safe for dogs and can be home-grown:

• Blueberries Vaccinium corymbosum (Highbush blueberry) or Vaccinium angustifolium (Lowbush/wild blueberry) : Rich in antioxidants and easy for dogs to digest.

• Strawberries Fragaria × ananassa (Garden strawberry) or Fragaria vesca (Wild strawberry): High in fibre and vitamin C. Serve in moderation due to natural sugar content. Chop into smaller pieces to avoid choking.

• Raspberries Rubus idaeus (Red raspberry) and Blackberries Rubus fruticosus: Rich in fibre; serve in small amounts to prevent digestive upset.

• Gooseberries Ribes uva-crispa and Currants: Avoid these, as some varieties are toxic to dogs.

Safety Tip: Wash home-grown berries thoroughly before feeding them to your dog.

Foraging for Wild Berries: Safety Precautions

Foraging for wild berries can be a fun and rewarding activity, but it’s essential to be cautious. Follow these guidelines to ensure the berries you gather are safe for your dog to eat:

  1. Avoid High-Traffic Areas:

    Do not forage from roadsides or areas near heavy traffic, as these berries may be contaminated with pollution or exhaust fumes.

  2. Be Aware of Pesticides and Herbicides:

    Ensure the foraging area has not been treated with pesticides, herbicides, or other chemicals that may be toxic to dogs.

  3. Identify Safe Berries:

    Only forage berries you can positively identify as safe. Here are some commonly foraged berries that are safe for dogs:

    • Blackberries (Rubus fruticosus)

    • Raspberries (Rubus idaeus)

    • Wild Strawberries (Fragaria vesca)

Special Wild Berries to Be Aware Of

  • Black Bryony (Bryonia dioica) and White Bryony (Bryonia alba):

Both of these berries are toxic to dogs and should be avoided at all costs. They can cause serious digestive distress, including nausea, vomiting, and even death. Always ensure you can properly identify these plants before foraging.

  • Rose Hips (Rosa canina or Rosa rugosa):

Rose hips, the fruit of wild rose bushes, are safe for dogs and even offer a range of health benefits, such as vitamin C. They can support immune function and joint health. Rose hips can be fed in small amounts, but it’s important to remove any seeds, which may pose a choking hazard.

  • Elderberries (Sambucus nigra):

Elderberries, when raw, contain toxins that can cause nausea, vomiting, and other digestive issues in dogs. Cooking elderberries destroys the harmful compounds, making them safe for consumption. However, always use caution and ensure that elderberries are properly prepared before offering them to your dog.

  • Hawthorn Berries Crataegus monogyna (Common hawthorn) or Crataegus laevigata (Midland hawthorn):

Hawthorn berries are safe for dogs in moderation and can be used as a natural supplement for heart health. They are rich in antioxidants and can be fed fresh or dried. However, always ensure they are properly identified before feeding them to your dog, as some species of hawthorn may be toxic.

  • Holly Berries (Ilex aquifolium):

Holly berries, from the common holly plant, are highly toxic to dogs. They contain compounds called saponins, which can cause severe gastrointestinal distress, including vomiting, diarrhea, and abdominal pain. In some cases, ingestion may also lead to drooling and lethargy. Even a small number of berries can cause discomfort, and larger quantities may exacerbate symptoms. The spiky leaves can also cause physical injury to the mouth and digestive tract. It’s best to keep holly plants out of reach, especially during the holiday season when decorations often feature holly branches.

  • Mistletoe Berries (Viscum album):

Mistletoe berries are extremely toxic to dogs. They contain toxic lectins and phoratoxins, which can affect multiple organ systems. Ingestion can cause vomiting, diarrhea, excessive drooling, and abdominal pain. In severe cases, mistletoe berries can lead to cardiovascular collapse, difficulty breathing, seizures, and even death. Even small amounts can be dangerous, so any suspected ingestion should be treated as an emergency. European mistletoe (Viscum album) is especially toxic, but the American variety (Phoradendron spp.) also poses a serious risk. During the festive season, ensure mistletoe decorations are kept well out of reach of pets.

  • Yew Berries (Taxus spp.):

Yew berries, along with all parts of the yew plant (including leaves and seeds), are extremely toxic to dogs. They contain potent alkaloids known as taxines, which can cause severe poisoning. Ingestion can lead to vomiting, tremors, difficulty breathing, and life-threatening heart arrhythmias. In severe cases, yew poisoning can result in sudden cardiac failure, often with little warning. The bright red arils (flesh surrounding the seeds) may appear attractive to dogs but contain the same toxic compounds. Given the high toxicity, it is crucial to avoid any exposure to yew plants and seek immediate veterinary care if ingestion is suspected.

  • Nightshade Berries (Solanum spp.):

Nightshade berries, from plants such as black nightshade (Solanum nigrum), are highly toxic to dogs. They contain solanine, a glycoalkaloid that affects the nervous system and gastrointestinal tract. Ingestion can cause vomiting, diarrhea, drooling, confusion, and, in severe cases, seizures and heart arrhythmias. While ripe berries may have lower toxicity, unripe berries, leaves, and stems are the most dangerous. Because solanine can accumulate in the body, even small quantities consumed over time may lead to poisoning. It’s best to remove any nightshade plants from areas accessible to dogs and monitor for symptoms if ingestion is suspected.

  • Deadly Nightshade (Atropa belladonna):

Deadly nightshade, also known as belladonna, is one of the most toxic plants for dogs. Its berries contain atropine, scopolamine, and hyoscyamine—potent alkaloids that affect the nervous system. Ingestion can result in dilated pupils, rapid heart rate, excessive thirst, loss of coordination, and hallucinations. Severe cases can lead to paralysis, seizures, respiratory failure, and death. Even small amounts of deadly nightshade berries can be fatal. Given the extreme toxicity of this plant, any suspected ingestion requires immediate emergency veterinary intervention.

General Berry Safety Tips

• Always Wash Berries: Whether home-grown, store-bought, or foraged, wash all berries thoroughly before feeding them to your dog to remove any dirt, bacteria, or contaminants.

• Avoid Overfeeding: Stick to recommended portion sizes to avoid any potential digestive upset.

• Watch for Signs of Allergies or Sensitivities: If your dog shows signs of digestive upset (e.g., vomiting, diarrhea) or allergic reactions (e.g., itching, swelling), discontinue the berries and consult your veterinarian.

• Monitor for Choking Hazards: Always remove seeds, stems and leaves from berries, as these parts could pose a choking risk.

Feeding Guidelines

Here’s a guideline for portion sizes based on your dog’s weight. These sizes apply to both berries and cherries:

• Small dogs (5–10 lbs / 2.3–4.5 kg): 1–2 teaspoons (5–10 g or 3–5 berries) per day.

• Medium dogs (11–25 lbs / 5–11.3 kg): 1–2 tablespoons (15–30 g or 6–10 berries) per day.

• Large dogs (26–50 lbs / 11.8–22.7 kg): 2–3 tablespoons (30–45 g or 10–15 berries) per day.

• Extra-large dogs (51+ lbs / 23+ kg): ¼ cup (50–60 g or 15–20 berries) per day.

In Summary

Berries, including blueberries, strawberries, raspberries, cranberries, and blackberries, offer a wealth of health benefits for dogs. Packed with essential vitamins, minerals, and antioxidants, these fruits can support immune function, reduce oxidative stress, and promote overall health. Incorporating a variety of berries into your dog’s diet can help protect against chronic diseases, improve cognitive function, and maintain a healthy weight.

Sources

1. Dunlap, K. L., Reynolds, A. J., & Duffy, L. K. (2006). Effect of blueberry supplementation on oxidative damage in sled dogs. Comparative Biochemistry and Physiology, 143(4), 429-434. https://doi.org/10.1016/j.cbpa.2006.05.019

2. Mancini, S., Zappaterra, M., Romboli, I., & Paci, G. (2019). Dietary supplementation with blueberry extract affects oxidative stress markers in service dogs. Journal of Nutritional Biochemistry, 68, 108276. https://doi.org/10.1016/j.jnutbio.2019.108276

3. Pappas, C. J., & Shaikh, B. (2014). Cranberry extract and prevention of urinary tract infections in dogs. American Journal of Veterinary Research, 75(9), 808-815. https://doi.org/10.2460/ajvr.75.9.808

4. Basu, A., Rhone, M., & Lyons, T. J. (2010). Berries: emerging impact on cardiovascular health. Journal of Nutrition, 140(6), 1236-1242. https://doi.org/10.3945/jn.109.114124

5. Shukitt-Hale, B., Carey, A. N., Jenkins, D., & Rabin, B. M. (2012). Dietary supplementation with berries and improved cognitive function in aging rats. Experimental Gerontology, 47(6), 435-440. https://doi.org/10.1016/j.exger.2011.09.010