Raisins, the dried form of grapes (Vitis vinifera L.), are a naturally sweet and shelf-stable fruit enjoyed globally. Not only are they convenient, but raisins are also a concentrated source of antioxidants and dietary fiber, contributing to multiple aspects of health including digestion, heart function, and bone strength.

Commonly made from Thompson Seedless grapes, raisins get their sweetness from naturally occurring sugars like fructose and glucose. Despite their sugar content, they have a low glycemic impact thanks to their fiber content.

Rich in Antioxidants

Raisins are especially high in polyphenols—compounds that act as antioxidants to counteract free radicals in the body. By reducing oxidative stress, these compounds help protect cells from damage and may lower the risk of chronic disease. Resveratrol, one such polyphenol in raisins, is noted for its heart-protective effects.

Drying grapes to make raisins concentrates their phytonutrients, making them a more compact source of antioxidants. However, some nutrients may degrade during drying, which is why pre-drying treatments are sometimes used to preserve quality.

Excellent Source of Dietary Fiber

Raisins provide both soluble and insoluble fiber, with approximately 4.5 grams of fiber per 100 grams—about 16% of the recommended daily intake. Soluble fiber supports healthy blood sugar and cholesterol levels, while insoluble fiber promotes bowel regularity.

Supports Gut Microbiome Health

The fiber in raisins, particularly fructans formed during the drying process, acts as a prebiotic—feeding beneficial gut bacteria. Research has shown that people who eat several servings of raisins a day may experience an increase in helpful bacteria like Faecalibacterium prausnitzii, which is linked to colon health.

May Help Regulate Blood Sugar

Although high in sugar, raisins have a low glycemic index, especially when eaten in moderate portions. Their fiber content helps slow sugar absorption, reducing blood sugar spikes. Some studies show that even people with diabetes can consume raisins without sharp increases in blood sugar or insulin levels.

Potential Cardiovascular Benefits

Adding raisins to your diet may support heart health. Their fiber and polyphenol content can help lower LDL (bad) cholesterol and blood pressure. Antioxidants like resveratrol may also reduce inflammation and support vascular health.

Contributes to Bone Health

Raisins contain nutrients vital to bone strength, including magnesium, calcium, potassium, and vitamin K. They’re also a good source of boron, a trace mineral involved in bone metabolism and hormone regulation. A 100-gram serving offers about 2.2 mg of boron, which supports the absorption of calcium and vitamin D.

Raisins vs. Sultanas

Sultanas (golden raisins) are made from the same type of grape as traditional dark raisins but are typically lighter in color and sweeter in taste. They are often treated with sulfur dioxide to preserve their golden hue. Nutritionally, they are similar, though dark raisins usually have more fiber and iron.

Raisins vs. Currants

Currants, also known as Zante currants, are smaller and derived from Black Corinth grapes. Despite their size, they are nutritionally comparable to raisins in terms of fiber, sugar, and antioxidant content. Because they are smaller, a portion by volume yields more currants than raisins.

Nutritional Profile

Here’s what 100 grams of seedless dark raisins provide:

  • Calories: 299

  • Total fat: 0.25 g

  • Sodium: 26 mg

  • Carbohydrates: 79.3 g

  • Fiber: 4.5 g

  • Sugars: 65.2 g

  • Protein: 3.3 g

  • Copper: 0.27 mg (30% DV)

  • Potassium: 744 mg (16% DV)

  • Magnesium: 36 mg (8.5% DV)

Raisins are low in fat and sodium, rich in potassium and fiber, and contain moderate amounts of calcium and magnesium—beneficial for heart and bone health.

Potential Risks

Allergic reactions to grapes or raisins are rare but possible. Some individuals may be sensitive to sulfites used in the drying process, which can trigger reactions in those with sulfite intolerance. Additionally, mold contamination during drying may affect people with mold allergies.

If you experience symptoms like hives, itching, or gastrointestinal discomfort after consuming raisins, consult a healthcare professional.

Ways to Eat Raisins

Raisins can be enjoyed as a snack or added to a variety of dishes:

  • Add to hot cereals like oatmeal during cooking

  • Sprinkle on parfaits or yogurt bowls

  • Use as a topping for leafy green or grain-based salads

  • Include in homemade muesli or granola

  • Replace chocolate chips in baked goods for added fiber

  • Combine with nuts and seeds in trail mix

  • Mix into savory dishes like couscous or tagines for a sweet contrast

Making Raisins at Home

If you’d like to make your own raisins:

  1. Wash and dry fresh grapes

  2. Pierce each grape to aid moisture release

  3. Place on a baking tray, lightly spray with oil

  4. Bake at 145°F (63°C) for 8 hours or until wrinkled and chewy

  5. Let them cool fully and store in an airtight container

A Quick Recap

Raisins are a naturally sweet, nutrient-dense dried fruit packed with fiber and polyphenols. They may support heart health, aid digestion, regulate blood sugar, and contribute to bone strength. Though generally safe, individuals sensitive to sulfites or mold should be cautious.

Enjoy raisins in cereals, salads, baked goods, or savory dishes—or make your own at home for a healthy, homemade treat.