Have not followed him in the past, but as an endurance athlete and recently retired health professional I found Dr. Attia's interview with Dr. van Loon (linked by Chucknut) both interesting and well-balanced. And generally consistent with my readings of the related medical/physiological academic literature. No heavy pushing of supplements or 'fad' diets but detailed explanations of actual data on muscle metabolism in response to exercise and the LACK thereof. Especially the increased importance of exercise (inc resistance training) and increased protein intake as we age. Great to hear him say that even 'old people muscles' can still respond positively to exercise and protein intake! But, as always, YMMV. Personally I cannot take in more than about 15g of protein shake after a workout without getting some GI distress so I also appreciated Dr. van Loon's comments that protein intake over the next many hours was just as beneficial over the course of days/weeks of an exercise program.
And of course- those with specific health issues (kidney, liver, heart, etc.) should always check with their doctor prior to making major changes in their diet, exercise, etc.