Tag Archives: review

Review: Inulin and FOS Mechanisms

Abstract

Inulin, oligofructose and bone health: experimental approaches and mechanisms.

Inulin-type fructans have been proposed to benefit mineral retention, thereby enhancing bone health. Many, but not all, experimental animal studies have shown increased mineral absorption by feeding non-digestible oligosaccharides. Possible reasons for inconsistencies are explored. A few studies have reported an enhanced bone mineral density or content. Bone health can be evaluated in chronic feeding studies with bone densitometry, bone breaking strength, bone mineral concentration and bone structure. Isotopic Ca tracers can be used to determine the point of metabolism affected by feeding a functional food ingredient. These methods and the effects of feeding inulin-type fructose are reviewed. Inulin-type fructans enhance Mg retention. Chicory long-chain inulin and oligofructose enhance femoral Ca content, bone mineral density and Ca retention through enhanced Ca absorption and suppressed bone turnover rates, but it is not bone-promoting under all conditions.

Weaver CM
Br. J. Nutr. Apr 2005
PMID: 15877902

Review: Inulin, Isoflavones, Calcium

Abstract

Inulin-type fructans and bone health: state of the art and perspectives in the management of osteoporosis.

If the primary role of diet is to provide sufficient nutrients to meet the metabolic requirements of an individual, there is an emerging rationale to support the hypothesis that, by modulating specific target functions in the body, it can help achieve optimal health. Regarding osteoporosis prevention, since Ca is most likely to be inadequate in terms of dietary intake, every strategy targeting an improvement in Ca absorption is very interesting. Actually, this process may be susceptible to manipulation by fermentable substrates. In this light, inulin-type fructans are very interesting, even if we need to gather more data targeting bone metabolism before health professionals can actively advocate their consumption to prevent senile osteoporosis. Besides targeting the prevention of postmenopausal osteoporosis, inulin-type fructans still remain a source for putative innovative dietary health intervention. Indeed, given in combination with isoflavones, they may have a potential for maintaining or improving the bone mass of human subjects, by modulating the bioavailability of phyto-oestrogens.

Coxam V
Br. J. Nutr. Apr 2005
PMID: 15877884

Review: Carbs, FOS and Inulin Beneficial for Bones

Abstract

Osteoporosis and intake of carbohydrates.

Adequate energy intake including carbohydrates is essential to maintain bone mass. Emaciation along with deficiency in nutrients, such as calcium, vitamin D, and protein is a significant risk factor for bone loss, and should be avoided.
However, there is no clinical evidence that shows the direct effects of carbohydrate on bone mass. On the other hand, excessive intake of carbohydrates results in obesity, which causes other metabolic diseases such as diabetes mellitus (DM). Therefore, dietary regimen must be balanced in general, and complications and conditions of individual patients should be taken well into account. In addition, energy intake is a basis for adequate exercise in order to maintain physical activity and ideal body weight, which will further decrease the risk of bone fracture. Some indigestible carbohydrates, such as inulin and oligofructose, are shown to increase the availability of minerals from foods, and thus can be beneficial to bone mass.

Nakayama K, Katayama S
Clin Calcium Apr 2005
PMID: 15802784

Review: Adding Calcium, Magnesium, Vitamin D, Vitamin K, Inulin, Protein, and Phytoestrogens to Foods

Abstract

Biomarkers of bone health appropriate for evaluating functional foods designed to reduce risk of osteoporosis.

Osteoporosis is a growing global problem. The health care costs and decreased productivity and quality of life are staggering. Much research is invested in life-style approaches to build peak bone mass during growth to prevent osteoporosis as well as to treat the disease in later life. Functional foods have enjoyed a niche in bone health. Foods fortified with Ca are most popular. Other bone nutrients such as vitamin D, Mg and vitamin K are sometimes added. Future products are likely to include enhancers of Ca absorption such as inulin or whey proteins. Dietary factors that reduce urinary Ca loss (plant proteins) or suppress bone resorption (possibly phyto-oestrogens) are also gaining attention. Methodologies for evaluating the effectiveness of functional foods on bone health include measures of bone quality such as bone densitometry or measures of Ca metabolism, particularly absorption. Biochemical markers for bone turnover are less satisfactory for diet-related effects. Use of a rare isotope, 41Ca, and accelerator mass spectrometry offers a new approach for assessing the ability of functional foods to suppress bone resorption.

Weaver CM, Liebman M
Br. J. Nutr. Nov 2002
PMID: 12495464

Review: FOS and Inulin, Minerals and Bones

Abstract

Inulin, oligofructose and mineral metabolism – experimental data and mechanism.

Numerous investigations performed in animal models in the past 10 years have shown repeatedly that non-digestible oligosaccharides (NDO), such as inulin, oligofructose or transgalacto-oligosaccharides (TOS), stimulate mineral absorption, mainly calcium and magnesium. Long-term beneficial effects on bone health have been indicated by accumulation of bone mineral content in growing rats or prevention of bone loss in ovariectomized rats. However, bone mineral content or density are not necessarily associated with bone quality. In recent studies both oligofructose and calcium prevented loss of trabecular bone area induced by oestrogen deficiency, this, however, occurred at different trabecular shapes. The effects of NDO on mineral metabolism may be based on the enhancement of passive and active mineral transport across the intestinal epithelium, mediated by an increase in certain metabolites of the intestinal flora and a reduction of pH. The possible impact of short-chain fatty acids, butyrate in particular, and of polyamines on the stimulation of mineral absorption capacity, and the interaction of oligofructose and antibiotics is discussed.

Scholz-Ahrens KE, Schrezenmeir J
Br. J. Nutr. May 2002
PMID: 12088516

Review: Milk + Resistance Training

Abstract

Impact of milk consumption and resistance training on body composition of female athletes.

Resistance exercise (RE) preceding the provision of high-quality dairy protein supports muscle anabolism. Milk contains bioactive components, including two high-quality protein fractions, calcium and vitamin D, each of which has been shown modulate body composition (increasing lean mass and decreasing fat mass) under energy balance and hypoenergetic conditions. These dairy nutrients are also essential for skeletal health. Acutely, no study of RE and milk/whey consumption has been undertaken exclusively in female athletes, let alone women, nevertheless, studies with both men and women show increased lean mass accretion following milk/whey compared to soy/placebo. Currently, no longer-term RE studies with milk supplementation have been done in female athletes. However, trials in young recreationally active women demonstrated augmented increases in lean mass and decreases in fat mass with RE and milk or whey protein consumption. The amount of protein consumed post-exercise is also important; two trials using yogurt (5 g protein/6 oz) failed to demonstrate a positive change in body composition compared to placebo. For bone health, RE plus dairy improved bone mineral density at clinically important sites and reduced bone resorption. With energy restriction, in one study, higher dairy plus higher protein resulted in greater fat loss, lean mass gain and improved bone health in overweight women. In another study, milk and calcium supplementation showed no greater benefit. Neither trial exclusively utilized RE. Overall, RE and milk/dairy consumption positively impact body composition in women by promoting losses in fat, gains or maintenance of lean mass and preservation of bone. Future studies in female athletes and under energy restriction with RE alone are warranted.

Josse AR, Phillips SM
Med Sport Sci 2012
PMID: 23075559

Review: Exercise Program Design

Abstract

Exercise for patients with osteoporosis: management of vertebral compression fractures and trunk strengthening for fall prevention.

Maintenance of bone health and quality requires mechanical strain, but the mechanical force needs to be within the bone’s biomechanical competence. In osteoporosis, compression of vertebral bodies can be insidious. Therefore, absence of pain does not necessarily indicate absence of vertebral microfracture and deformity. Further, patients with previous vertebral fractures are at risk for further vertebral fractures and their associated morbidity. Exercise is a part of the comprehensive management of patients with osteoporosis and has been associated with improvement of quality of life and lowered risk of future fracture. The exercise prescription needs to match the needs of the patient. If exercise is not prescribed properly, then it may have negative consequences. In general, an exercise program, therapeutic or recreational, needs to address flexibility, muscle strength, core stability, cardiovascular fitness, and gait steadiness. As with pharmacotherapy, therapeutic exercises need to be individualized on the basis of musculoskeletal status and an individual’s exercise interest. In osteoporosis, axial strength and stability are of primary importance. In particular, a spinal extensor strengthening program should be performed with progressive measured resistance as tolerated. To address falls and fractures, an exercise program should also include balance and lower extremity strength training. Proper dosing of oral cholecalciferol and calcium supplements can enhance the effect of strengthening exercises. Finally, a coordinated approach, such as the Spinal Proprioception Extension Exercise Dynamic (SPEED) program, can improve back extensor strength, the level of physical activity, and locomotion, and reduce back pain and fear and risk of falls.

Sinaki M
PM R Nov 2012
PMID: 23174554

Review: Exercise and Bone Markers

Abstract

Bone metabolism markers in sports medicine.

Bone mass can be viewed as the net product of two counteracting metabolic processes, bone formation and bone resorption, which allow the skeleton to carry out its principal functions: mechanical support of the body, calcium dynamic deposition and haemopoiesis. Besides radiological methods, several blood and urinary molecules have been identified as markers of bone metabolic activity for estimating the rates and direction of the biological activities governing bone turnover. The advantages for the use of bone metabolism markers are that they are potentially less dangerous than radiological determinations, are more sensitive to changes in bone metabolism than radiological methods and are easily collected and analysed. The disadvantages are that they have high biological variability. Physical exercise is a known source of bone turnover and is recommended for preventing osteoporosis and bone metabolism problems. There are numerous experiments on bone metabolism markers after acute exercise, but not after long-term training and during or after a whole competition season. Moreover, few studies on bone metabolism markers have evaluated their performance in elite and top-level athletes, who have a higher bone turnover than sedentary individuals. Despite discrepant results among studies, most have shown that short exercise is insufficient for modifying serum concentrations of bone metabolism markers. Marker variations are more evident after several hours or days after exercise, bone formation markers are more sensitive than bone resorption markers, and stimulation of osteoblast and/or osteoclast functions is exercise dependent but the response is not immediate. The response depends on the type of exercise; the markers seem to be less sensitive to resistance exercise and the intensity of exercise is not discriminate. Comparisons between trained subjects and untrained controls have demonstrated the influence of exercise on bone turnover. During training, carboxy-terminal collagen cross-links (CTx), a bone resorption marker, was shown to be less sensitive than amino-terminal cross-linking telopeptide of type I collagen (NTx) and urinary pyridinolines, which were sensitive to anaerobic exercise. Whereas, the bone formation markers, bone alkaline phosphatase (BAP) and osteocalcin (OC) changed after 1 month and 2 months of an exercise programme, respectively. After 2 months, while BAP normalized, it was found to be sensitive to aerobic exercise and OC was found to be sensitive to anaerobic exercise. After prolonged training and competition, bone formation markers are found to change in sedentary subjects enrolled in a physical activity programme. Professional athletes show changes in bone formation markers depending on programme intensity, whereas bone resorption appears to stabilize. Crucial for long-term training, are the characteristics of exercise (e.g. weight-bearing, impact).

Banfi G, Lombardi G, Colombini A, Lippi G
Sports Med Aug 2010
PMID: 20632739

Review: Exercise & Bones

Abstract

The effect of physical activity and its interaction with nutrition on bone health.

Physical activity (PA) is a popular therapy for the prevention and treatment of bone loss and osteoporosis because it has no adverse side effects, it is low cost, and it confers additional benefits such as postural stability and fall prevention. Bone mass is regulated by mechanical loading, and is limited but not controlled by diet. The mechanism by which strain thresholds turn bone remodelling ‘on’ and ‘off’ is known as the mechanostat theory. Research in animals has shown that optimal strains are dynamic, with a high change rate, an unusual distribution and a high magnitude of strain, but the results of randomized controlled trials in human subjects have been somewhat equivocal. In the absence of weight-bearing activity nutritional or endocrine interventions cannot maintain bone mass. Biochemical markers of bone turnover predict bone mass changes, and findings from our research group and others have shown that both acute and chronic exercise can reduce bone resorption. Similarly, Ca intervention studies have shown that supplementation can reduce bone resorption. Several recent meta-analytical reviews concur that changes in bone mass with exercise are typically 2-3%. Some of these studies suggest that Ca intake may influence the impact of PA on bone, with greater effects in Ca-replete subjects. Comparative studies between Asian (high PA, low Ca intake) and US populations (low PA, high Ca intake) suggest that PA may permit an adaptation to low Ca intakes. Whether Ca and PA interact synergistically is one of the most important questions unanswered in the area of lifestyle-related bone health research.

Murphy NM, Carroll P
Proc Nutr Soc Nov 2003
PMID: 15018482

Review: Phytonutrients

Abstract

Phytonutrients for bone health during ageing.

Osteoporosis is a skeletal disease characterized by a decrease in bone mass and bone quality that predispose an individual to an increased risk of fragility fractures. Evidence demonstrating a positive link between certain dietary patterns (e.g. Mediterranean diet or high consumption of fruits and vegetables) and bone health highlights an opportunity to investigate their potential to protect against the deterioration of bone tissue during ageing. While the list of these phytonutrients is extensive, this review summarizes evidence on some which are commonly consumed and have gained increasing attention over recent years, including lycopene and various polyphenols (e.g. polyphenols from tea, grape seed, citrus fruit, olive and dried plum). Evidence to define a clear link between these phytonutrients and bone health is currently insufficient to generate precise dietary recommendations, owing to mixed findings or a scarcity in clinical data. Moreover, their consumption typically occurs within the context of a diet consisting of a mix of phytonutrients and other nutrients rather than in isolation. Future clinical trials that can apply a robust set of outcome measurements, including the determinants of bone strength, such as bone quantity (i.e. bone mineral density) and bone quality (i.e. bone turnover and bone microarchitecture), will help to provide a more comprehensive outlook on how bone responds to these various phytonutrients. Moreover, future trials that combine these phytonutrients with established bone nutrients (i.e. calcium and vitamin D) are needed to determine whether combined strategies can produce more robust effects on skeletal health.

Sacco SM, Horcajada MN, Offord E
Br J Clin Pharmacol Mar 2013
PMID: 23384080