At present, very few epidemiologic intervention studies have been done with humans concerning the use of Spirulina for health benefits. Hirahashi et al.52 reported on the molecular mechanism of the human immune potentiating capacity of Spirulina. NK-mediated cytolysis and IFN y production of NK cells collected from 12 healthy volunteers (age 40-65 years) who continued daily drinking of 50 ml of a hot-water extract of Spirulina were assayed. Enhancements of NK-mediated cytolysis and IFN y production were observed in more than 50% subjects 2 months after the beginning of administration. In a study in India,53 an experiment for assessment of S.fusiformis as a source of vitamin A was performed using six healthy preschool children aged 3-5 years as subjects. After stabilization by an almost carotene-free diet taken for 7 days, a single dose of Spirulina powder containing 1.2 mg of vitamin A fed along with each morning meal for 1 month improved serum retinol levels significantly, from 21.4 ± 6.23 to 30.3 ± 6.88 of retinol ^g/dl. Average absorption rate of total carotene was 72.3%, which was almost the same as that observed in a vitamin A-directly supplemented group, suggesting the potential use of Spirulina as a dietary source of provitamin A. Nakaya et al.54 reported a cholesterol lowering effect of Spirulina in studies of 30 healthy Japanese male volunteers as subjects who had mild hyperlipidemia or mild hypertension. Total serum cholesterol level and low-density lipoprotein (LDL) cholesterol were significantly reduced, while neither high-density lipoprotein (HDL)-cholesterol nor triglyceride was changed by 4.2 g of Spirulina administration per day for 4 or 8 weeks. Another intervention study was carried out to assess the effect of Spirulina on lipid metabolism, antioxidant capacity, and immune function in elderly Koreans.55 About 6 male and 6 female subjects between the ages of 65-70 were given 7.5 g of Spirulina per day for 6 months. Concentrations of triglycerides, and total- and LDL-cholesterol in plasma decreased 4 weeks after the beginning of supplementation. Antioxidant capacity improved, and peripheral blood lymphocyte proliferation rate and plasma C3 levels detected as immune functions were also increased. Recently, Mao et al.56 found that daily feeding of Spirulina 1000 mg or 2000 mg as dietary supplement for 12 weeks in allergic individuals of 36 patients reduced IL-4 production in peripheral blood lymphocytes, while it seemed to be ineffective for the secretion of Th1 cytokines, IFNy and IL-2, indicating suppression of the differentiation of Th2 cells mediated, in part, by inhibiting the production of IL-4.
Nourishment should be taken essentially by diet. However, reflecting busy life styles of people today and their preferences in healthcare, especially in current aging society, eating habits have changed in developed nations in particular, and opportunities for using so-called health food supplements have increased. Through many studies using experimental animals and in some human studies, we have demonstrated the potential application of Spirulina (Arthrospira) as a nutritional and therapeutic supplement. We now expect Spirulina not only to be utilized effectively for people recovering from illness or for those in an unhealthy state but also for sustaining a healthy state among the general public, including the elderly. It is necessary to accumulate further data and evaluate it scientifically, from the viewpoints of evidence-based nutrition (EBN) and evidence-based healthcare (EBH), in order to assure the proper assessment and utilization of health foods.
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All you need is a proper diet of fresh fruits and vegetables and get plenty of exercise and you'll be fine. Ever heard those words from your doctor? If that's all heshe recommends then you're missing out an important ingredient for health that he's not telling you. Fact is that you can adhere to the strictest diet, watch everything you eat and get the exercise of amarathon runner and still come down with diabetic complications. Diet, exercise and standard drug treatments simply aren't enough to help keep your diabetes under control.