Okinawa streets ,Okinawa, Japan
Sean Cate
Sean Cate
July 14, 2023 ·  4 min read

This Barely Eaten Vegetable is a Key Longevity Secret for Okinawans Living in the Blue Zone

The southern islands of Japan are home to the Okinawans, a community known for their extraordinary longevity. Referred to as the “land of immortals” in the past, Okinawans have lower rates of cancer, heart disease, and dementia compared to Americans, with women on the islands living longer than any other women on the planet.1 The Okinawans’ longevity can be attributed to various factors, including their strong social connections and sense of purpose in life. However, one key element that stands out is their unique diet, with a particular emphasis on a food that is often passed over: the purple sweet potato.

The Okinawans Lifestyle for Longevity

Okinawans have established a lifestyle and environment that promotes long and healthy lives. They embrace an “ikigai,” a strong sense of purpose in life that provides them with clear roles and responsibilities well into their 100s.2 This sense of purpose keeps them active and engaged. Furthermore, Okinawans rely on a plant-based diet consisting of stir-fried vegetables, sweet potatoes, and tofu. Their meals are high in nutrients and low in calories, toting overall health and longer life.3

The Benefits of the Okinawans’ Diet

  • Nutritional Powerhouse: The Okinawa diet, including the purple sweet potato, provides a wide range of essential nutrients, including vitamins, minerals, and antioxidants. It helps with overall health and well-being.
  • Blood Sugar Regulation: Purple sweet potatoes have a lower glycemic index compared to other potato varieties, meaning they have a lesser impact on blood sugar levels. This is beneficial for maintaining stable blood sugar and reducing the risk of diabetes.
  • Antioxidant-Rich: Purple sweet potatoes are packed with antioxidants, particularly anthocyanins, which have been linked to better heart health, reduced risk of chronic diseases, and enhanced vision.
  • Blood Pressure Management: The potassium content in purple sweet potatoes and their polyphenolic compounds may help regulate blood pressure and improve cardiovascular health.
  • Potential Cancer Prevention: Some compounds found in purple sweet potatoes, such as anthocyanins and other antioxidants, have shown promise in stopping and fighting certain types of cancer, though more research is needed.
  • Fiber Boost: Purple sweet potatoes, like other varieties, are a good source of dietary fiber, which aids in digestion, helps maintain healthy cholesterol levels, and promotes satiety.
  • Resistant Starch: Purple sweet potatoes contain resistant starch, a type of fiber that acts as a prebiotic and supports gut health, contributing to overall well-being.

The Power of the Purple Sweet Potato

The purple sweet potato, a staple in the Okinawan diet, plays a significant role in their longevity. This vibrant tuber is rich in antioxidants and compounds that lower blood sugar levels, making it a valuable addition to their meals. While the centenarian Okinawans do consume some pork, it is reserved for ceremonial occasions and in small amounts. The purple sweet potato stands out as a nutritional powerhouse and a key component of their diet.

Read: 13 Foods The Longest Living People In The World Eat Everyday

How to Incorporate Purple Sweet Potatoes into Your Diet

While purple sweet potatoes may not be as commonly found as their orange counterparts, they are becoming more accessible in supermarkets and farmers’ markets. Here are some suggestions on how to incorporate these nutritional powerhouses into your diet:

  • Roasted Delight: Cut purple sweet potatoes into wedges or cubes, toss them with olive oil, sprinkle with your favorite herbs and spices, and roast them in the oven until tender. This method brings out their natural sweetness and enhances their flavor.
  • Mashed Goodness: Boil or steam purple sweet potatoes until they are soft, then mash them with a little butter or olive oil, salt, and pepper. You can also add a touch of cinnamon or nutmeg for extra flavor.
  • Colorful Salads: Slice or cube cooked purple sweet potatoes and add them to your salads for a vibrant burst of color. They pair well with leafy greens, cherry tomatoes, avocado, and a tangy vinaigrette.
  • Purple Power Smoothies: Blend cooked and cooled purple sweet potatoes with your favorite fruits, such as bananas or berries, along with some almond milk or yogurt for a nutritious and visually appealing smoothie.
  • Steamed or Boiled: Simply steam or boil purple sweet potatoes until tender and enjoy them as a side dish or incorporate them into grain bowls, stir-fries, or vegetable medleys.
  • Baked Goods: Purple sweet potatoes are useful in baking as well. Add them to muffins, pancakes, bread, or even desserts like pies and cakes for a delightful twist and added nutrients.

Remember to store purple sweet potatoes in a cool, dark place and consume them within a reasonable time frame to maintain their freshness and nutritional value.

By experimenting with different recipes and cooking methods, you can add the health benefits of purple sweet potatoes to your diet while enjoying their unique taste and vibrant color.


The Okinawans’ remarkable longevity is a result of their unique lifestyle and diet. Their strong social connections, sense of purpose, and focus on nutritious foods, particularly the purple sweet potato, contribute to their exceptional health and longevity. Incorporating elements of the Okinawan lifestyle, such as embracing a sense of purpose, maintaining a plant-based diet, and recognizing the benefits of the purple sweet potato, may hold the key to promoting longevity and well-being in our own lives. By following these practices, we can learn from the Okinawans and strive to live longer, healthier lives.

Keep Reading: The 3 Types of Tea That the Longest-Living People on the Planet Drink Most


  1. Okinawa, Japan Secrets of the world’s longest-living women..” Blue Zones
  2. Want to live a long, healthy life? 6 secrets from Japan’s oldest people.” We Forum. September 29, 2021.
  3. What Is the Okinawa Diet? Foods, Longevity, and More.” Healthline. Ansley Hill, RD, LD. July 11, 2023.
  4. Purple Power: 7 Benefits of Purple Potatoes.” Healthline.  Anne Danahy, MS, RDN. November 20, 2019