Surprising Health Benefits of Black Raspberries

Black raspberries, when compared to more well-known red raspberries or blackberries, may surprise you for their sweet delicious taste as well as their strong health properties

Black and red raspberries are varieties from the same Rubus family so their nutritional contents, such as calories, proteins, fiber and vitamins, are the same.

However, some components of black raspberries are completely different compared to the red variety -- they have a 10-fold increase in anthocyanins, nearly double the amount of ellagic acid and three times the antioxidant power, measured by their oxygen radical absorption capacity (ORAC) -- their ability to absorb free radicals (Table 1).

Blackberries and black raspberries look much the same, but all raspberries have a hollow core once they are off the vine, while blackberries have a non-hollow white or green core. Black raspberries have double the anthocyanins and nearly three times the antioxidant levels of blackberries.

Blackberries are unique because they have almost three times the vitamin K level as both raspberry varieties (see Table 1 for the differences between black raspberries, blackberries and red raspberries).

Antioxidants have been shown to fight cancer, heart disease and age-related decline. Anthocyanins, which give the black raspberry its rich dark purple color, protect against oxidative stress and are natural antioxidants. In addition to their antioxidant properties, black raspberries have chemopreventive, anti-inflammatory and neuroprotective effects and can lower the risk for breast and colorectal cancers and cardiovascular diseases.

In the most recent scientific findings, researchers have discovered that black raspberries are also highly effective in fighting oral cancers, preventing diabetes, lowering blood pressure, managing weight, alleviating skin allergies and decreasing bone loss.

Table 1. Differences Between Black Raspberries, Blackberries and Red Raspberries

Black Raspberries Blackberries Red Raspberries

Factors 1 cup raw 1 cup raw 1 cup raw

Calories 64 62 64

Protein 1.5 g (grams) 2 g 1.5 g

Fat 0.8 g 0.7 g 0.8 g

Carbs 14.7 g 13.8 g 14.7 g

Fiber 8 g, 29% of RDI 7.6 g, 27% of RDI 8 g, 29% of RDI

Vitamin C 32.2 mg, 36% of RDI 30.2 mg, 34% of RDI 32.2 mg, 36% of RDI

Vitamin K 9.6 mcg, 12% of RDI 28.5 mcg, 35% of RDI 9.6 mcg, 12% of RDI

Vitamin E 1.1 g, 7% of RDI 1.7 g, 11% of RDI 1.1 g, 7% of RDI

Taste Sweetest Less Sweet Sweet

Anthocyanin 214-589 mg/100g 109-155 mg/100g 20-65 mg/100g

Ellagic Acid 5.37 mg/g dry weight 5.83 mg/g dry weight 3.39 mg/g dry weight

ORAC 77 umole TE/g 28 umole TE/g 24 umole TE/g

Fights Oral Cancers

Common oral squamous cell cancers are found in the mouth, pharynx and esophagus. In a study of mice with tobacco smoke toxin-induced oral cancer, the group given 5% dietary black raspberry had significantly lower levels of DNA damage in the oral cavity and oral tumors decreased from 70% to 46.7%.

Anti-apoptotic and pro-inflammatory biomarkers for oral cancer were significantly reduced following freeze-dried black raspberry powder oral administration in a daily dissolvable lozenge for approximately two weeks in 30 patients who had been diagnosed with oral cancer and were scheduled for oral surgery.

In a carcinogen-induced study of oral cancer in hamster cheek pouches, hamsters were topically treated with freeze-dried black raspberry solution for 12 weeks and had significantly reduced multiplication of squamous cancer cells (41%), tumors (37%) and cell proliferation rate (nearly 7%), showing its prevention potential for oral cancer in humans.

In a trial of 20 Barrett's esophagus patients administered black raspberries, either 32 grams (g) or 45 g for six months, the black raspberry treatment significantly reduced lipid peroxidation -- linked to oxidative stress and free radical damage and significantly increased GST-pi levels, a marker of detoxification -- in 55% of the subjects, thus being helpful in preventing progression to esophagus cancer.

Freeze-dried black raspberries, and their components of anthocyanins and protocatechuic acid, were administered to carcinogen-induced esophageal cancer rats and all three treatments were found to inhibit the cancer by decreasing the proinflammatory and anti-inflammatory cytokines and increasing immune cell trafficking into the tumor tissues.

In an induced oral cancer mouse model, black raspberry extract demonstrated a strong cancer prevention ability by inhibiting the effects of the carcinogen and repairing bulky lesions in mouse DNA.

Prevents Diabetes

In a 12-week trial of 45 prediabetic patients administered an oral placebo, low dose -- 900 milligrams (mg) daily -- or a high dose -- 1,800 mg daily -- of black raspberry extract, the two black raspberry groups had dose-dependent improvements in control of glucose and lipid profiles and lower vascular inflammation.

Obese diabetic mice were fed black raspberry seed oil, either 8% or 16% of their total diet, or soybean oil in the control group and both the black raspberry seed oil groups showed stronger anti-inflammatory effects compared to the control group.

Three cohort studies reporting dietary anthocyanin intake with 200,894 participants and 12,611 Type 2 diabetes cases, and five cohort studies reporting berry intake with 194,019 participants and 13,013 diabetic cases, were investigated.

Researchers found that dietary anthocyanin and berry consumption were associated with a 15% and 18% reduction, respectively, in Type 2 diabetes risk. Similarly, in a meta-analysis of 23 studies, berries were highly effective in lowering risk for Type 2 diabetes.

Lowers Blood Pressure

The use of black raspberry in the form of dried powder capsules significantly lowered 24 hour and nighttime systolic blood pressure compared to a placebo in a study of 45 prehypertensive patients during eight weeks of treatment.

In a cross-sectional study of dietary patterns of 1,898 women aged 18 to 75 years, higher anthocyanin intake (readily available in black raspberries) was associated with significantly lower systolic blood pressure.

Reduces Obesity

In an eight-week in vitro study of high fat diet-induced obese mice, black raspberry (10 mg and 50 mg per kilogram daily) produced dose-dependent decreases in body weight, food efficiency ratio, adipose tissue weight, serum glucose, total cholesterol levels, total triglycerides and low-density lipoproteins.

Similarly, a polyphenol enriched herbal complex (containing ellagic acid, Bunge, vitexin, chlorogenic acid and cinnamic acid) also decreased obesity and metabolic dysfunction in a high-fat diet-induced obese mouse model.

Mice were fed a high-fat diet to induce hyperlipidemia and orally administered black raspberry extract as a treatment and rosuvastatin, a cholesterol synthesis inhibitor, as a control. Black raspberries normalized immune processes, lymphocyte proliferation and cytokine production and decreased the elevated serum tumor necrosis factor and total cholesterol, making it an effective natural alternative comparable to the statin control drug.

Stops Osteoporosis

Administration of black raspberry extract in a prostate disease-induced rat model effectively inhibited osteoporosis (prostate patients have increased risk for bone loss) by altering the activation of osteoblasts and osteoclasts.

Black raspberry vinegar was tested as a treatment (low dose and high dose) against alendronate (a postmenopausal osteoporosis drug) and no treatment groups in an ovariectomized rat model.

Compared to the placebo, the low and high dose black raspberry vinegar groups showed positive effects on estrogen regulation and were comparable to the effects of the alendronate treatment. Black raspberry vinegar is recommended as an effective non drug alternative for the prevention of osteoporosis in postmenopausal women.

Inhibits Skin Allergies

Using an in vivo mouse model of induced-contact hypersensitivity, black raspberries or their anthocyanin components were added to their diet. Both fruit-based supplements improved symptoms such as swelling, rash, redness, itching and skin patches caused by the skin inflammation and are potentially safer than current steroid dermatitis treatments.

Black raspberry extracts were tested for their anti-inflammatory effects and results showed that three anthocyanin components were key to controlling inflammation. They suppressed inducible nitric oxide synthase (balances the free radicals in your body), tumor necrosis factor and interleukin expressions (regulators of inflammation), which explains the health benefits of the extracts in inflammatory diseases.

Beneficial Health Properties

Black raspberries' top health properties include having anti-inflammatory, antioxidant, chemopreventive and anticarcinogenic effects.

These benefits give black raspberries their amazing abilities to fight cancers, control blood pressure, reduce weight, strengthen bones, improve skin health and help prevent diabetes and cardiovascular diseases. For more details, please consult GreenMedInfo.com's research database on black raspberries.