Oh King of Edible Leaves, His Majesty The Spinach
Succession

This dark green leafy vegetable with its mild, slightly bitter taste, has been cherished for its health benefits for centuries. Originating from ancient Persia, spinach (Spinacia oleracea) was introduced to Europe in the 12th century and quickly became a staple in various cuisines due to its versatility and rich nutrient profile. Today, spinach continues to be a popular leafy green, renowned not only for its culinary uses but also for its remarkable health benefits.

Its rich vitamin and mineral profile, along with its antioxidant and fibre content, make it an excellent addition to the Well Dog Pantry. Avoid overfeeding: owing in particular to its oxalate content, spinach should be fed in moderation as part of a balanced diet in combination with other foods.

Main Nutrients
Fibre
Spinach is a good source of dietary fibre, which plays a vital role in maintaining digestive health in dogs. The fibre content in spinach helps regulate bowel movements, prevent constipation, and support overall gastrointestinal function. The fibre in spinach can also act as a prebiotic, promoting the growth of beneficial gut bacteria, which is crucial for maintaining a healthy digestive system in dogs.
Antioxidants
Spinach is rich in antioxidants such as flavonoids, carotenoids, and phenolic compounds. These antioxidants help neutralise free radicals, reduce oxidative stress, and support overall cellular health. Antioxidants are essential for protecting dogs from various diseases, including certain cancers, and promoting longevity by reducing inflammation and supporting immune function.
Bioactive Compounds
Spinach contains several bioactive compounds, including lutein and zeaxanthin, which are known to support eye health. These compounds help protect the eyes from damage caused by ultraviolet light and oxidative stress, contributing to healthy vision in dogs.

Main Vitamins
Vitamin A
Spinach is a rich source of beta-carotene, a precursor to vitamin A. This vitamin is crucial for maintaining healthy vision, skin, and immune function in dogs. Vitamin A also supports the development and maintenance of healthy mucous membranes, which act as a barrier against infections.
Vitamin K
Vitamin K is abundant in spinach and plays a significant role in blood clotting and bone health. Whilst dogs are able to synthesise some vitamin K in a healthy gut, it may not always be enough for their overall nutritional requirements. and factors such as diet, gut health and antibiotic use may affect a dog’s ability to produce and/or absorb sufficient vitamin K. As vitamin K is not stored in large amounts,  dietary intake will also ensure adequate levels.
Vitamin C
As an antioxidant, vitamin C in spinach is a defence mechanism against free radicals, supports the immune system, and contributes to the overall cellular health of dogs. Although dogs can synthesise vitamin C in the liver naturally, additional dietary sources can be beneficial, especially in times of stress or illness.
Folate (Vitamin B9) and Vitamin B6
Folate is essential for DNA synthesis and repair, cell division, and red blood cell formation. It is particularly important for pregnant dogs, as it supports healthy foetal development. Vitamin B6 plays a crucial role in amino acid metabolism, neurotransmitter synthesis, and red blood cell production. It also supports the immune system and helps maintain healthy brain function in dogs.
Minerals
Calcium
Calcium is critical for bone health, teeth, muscle function, nerve transmission and even blood clotting. Spinach contains calcium, which supports the structural integrity of bones and teeth in growing and aging dogs alike. However, it is important to note that spinach also contains oxalates, which can bind to calcium and reduce its absorption, so it should be fed in moderation.
Magnesium
Magnesium is essential for many biological processes, including energy production, muscle contraction, and nerve function. It also plays a role in maintaining healthy bones and teeth. Magnesium supports the overall well-being of dogs by aiding in the absorption of other minerals and vitamins.

Benefits – Key Takeaways:

Immune Support
The array of vitamins and antioxidants found in spinach significantly bolsters immune function in dogs. Vitamin C, a potent antioxidant, enhances the immune system’s ability to fend off infections and diseases. Additionally, the beta-carotene in spinach, which converts to vitamin A, supports the development and maintenance of healthy mucous membranes, acting as a barrier against pathogens. The overall antioxidant profile of spinach helps reduce inflammation and supports the immune system in maintaining optimal health, thereby contributing to a robust defence mechanism against various illnesses.
Eye Health
The lutein and zeaxanthin in spinach are particularly beneficial for eye health. These antioxidants help protect the eyes from damage caused by ultraviolet light and oxidative stress, contributing to healthy vision in dogs. Regular consumption of spinach can help reduce the risk of age-related eye issues, ensuring that dogs maintain good eyesight as they age.
Bone Health
Spinach contributes to bone health due to its high vitamin K and calcium content. Vitamin K supports bone metabolism and helps maintain bone density, while calcium is essential for the structural integrity of bones and teeth. This makes spinach a valuable addition to the diet of growing puppies and aging dogs, helping prevent bone-related issues and maintaining overall skeletal health.
Digestive Health
The dietary fibre in spinach aids in maintaining a healthy gut microbiome by supporting the growth of beneficial bacteria in the intestines. This enhances the digestive process, improves nutrient absorption, and helps regulate bowel movements, reducing the risk of constipation and promoting a smooth digestive tract. Because fibre also aids in preventing the growth of harmful bacteria, this maintains a balanced and healthy gut environment, which is crucial for overall digestive health and the wellbeing of dogs.
Cardiovascular Health
The potassium in spinach supports heart health by helping to regulate blood pressure and maintain proper heart function. Potassium is essential for muscle contractions, including the heart muscle, and helps maintain electrolyte balance. This makes spinach beneficial for maintaining a healthy cardiovascular system in dogs.

A note about iron:

You might be wondering why iron isn’t included – after all, spinach is famously considered to be a good source of iron.  Myth 1.

And spinach was chosen by Popeye for its iron content. Myth 2![1].

In fact, at 1.26 mg for baby spinach and 1.05 mg for mature spinach (source FDA), these are not appreciable amounts. Added to that the barriers to absorption (thought to be caused by the oxalates and more recently attributed to the polyphenols in spinach[2][3]), these green leaves are super nutritious, but not for their iron content.

References:

[1] https://www5.in.tum.de/~huckle/Sutton_Spinach_Iron_and_Popeye_March_2010
[2] Gillooly, Marion et al. “The effects of organic acids, phytates and polyphenols on the absorption of iron from vegetables.” British Journal of Nutrition 49 (1983): 331 – 342.
[3] Brune M, Rossander L, Hallberg L. Iron absorption and phenolic compounds: importance of different phenolic structures. Eur J Clin Nutr. 1989 Aug;43(8):547-57. PMID: 2598894.

 

Want to know more? These studies might be useful:

  • Murakami C, Kumagai T, Hada T, Kanekazu U, Nakazawa S, Kamisuki S, Maeda N, Xu X, Yoshida H, Sugawara F, Sakaguchi K, Mizushina Y. Effects of glycolipids from spinach on mammalian DNA polymerases. Biochem Pharmacol. 2003 Jan 15;65(2):259-67. doi: 10.1016/s0006-2952(02)01483-1. PMID: 12504801.
  • Taís Motta Fernandes, Bárbara Bicalho Gomes, Ursula Maria Lanfer-Marquez, Apparent absorption of chlorophyll from spinach in an assay with dogs, Innovative Food Science & Emerging Technologies, Volume 8, Issue 3, 2007, Pages 426-432, ISSN 1466-8564, https://doi.org/10.1016/j.ifset.2007.03.019

 

Nutritional information, 100 g
Spinach, raw
For full nutrient content see Food Data Central (raw) and Food Data Central (boiled).

 

 

Important Considerations:

  • Always consult your veterinarian before making any significant dietary changes, particularly where there are pre-existing health conditions or dietary restrictions.
  • As some commercial foods contain spinach as an ingredient, check the label to see whether it’s in your dog’s food before giving more. Excessive intake of any foods can have adverse effects.
  • Ensure (where possible) that you use high-quality, organic products specifically formulated for pets (or better still, human grade ingredients) to avoid any potential adverse effects.
  • Introduce new foods gradually to avoid adverse effects such as gastrointestinal upset or diarrhoea.
  • I provide nutritional information purely as a helpful guide. Nutritional information on ingredients is obtained from the US Department of Agriculture’s FoodData Central site (https://fdc.nal.usda.gov/index.html) and any nutritional information provided in recipes is based on an online calculator: calories and other information will vary based on brands, ingredients and other factors.
  • Check nutrient levels and recommendations for your dog’s weight, age and activity. For example this nutritional guideline produced by FEDIAF.